diff --git a/app/package.json b/app/package.json
index fdc5aae554..be67038a9e 100644
--- a/app/package.json
+++ b/app/package.json
@@ -18,8 +18,8 @@
     "clean": "rm -fr node_modules .turbo build .swc"
   },
   "devDependencies": {
-    "@types/react-redux-toastr": "^7.0.0",
     "@swc/plugin-styled-components": "1.5.111",
+    "@types/react-redux-toastr": "^7.0.0",
     "@vitejs/plugin-react-swc": "^3.3.2",
     "eslint": "^8.56.0",
     "eslint-config-prettier": "^9.1.0",
@@ -72,6 +72,7 @@
     "react-tooltip": "^4.5.1",
     "reactstrap": "8.10.1",
     "redux": "4.2.1",
+    "redux-thunk": "^2.4.0",
     "regenerator-runtime": "0.13.9",
     "remark-gfm": "^4.0.0",
     "slugify": "^1.6.5",
diff --git a/app/src/Espace.jsx b/app/src/Espace.jsx
index 498bc69c7c..9890adbfb2 100644
--- a/app/src/Espace.jsx
+++ b/app/src/Espace.jsx
@@ -1,6 +1,6 @@
 import React, { lazy, Suspense, useEffect, useState } from "react";
-import { useSelector } from "react-redux";
-import { getCohort } from "./utils/cohorts";
+import useAuth from "./services/useAuth";
+import useCohort from "./services/useCohort";
 import API from "./services/api";
 import { ENABLE_PM, FEATURES_NAME, YOUNG_STATUS, isFeatureEnabled, permissionPhase2, shouldReAcceptRI } from "./utils";
 import { Redirect, Switch } from "react-router-dom";
@@ -34,8 +34,8 @@ const Espace = () => {
   const [isModalCGUOpen, setIsModalCGUOpen] = useState(false);
   const [isModalRIOpen, setIsModalRIOpen] = useState(false);
 
-  const young = useSelector((state) => state.Auth.young);
-  const cohort = getCohort(young.cohort);
+  const { young } = useAuth();
+  const { cohort } = useCohort();
 
   const handleModalCGUConfirm = async () => {
     setIsModalCGUOpen(false);
@@ -69,7 +69,7 @@ const Espace = () => {
 
   if (young.status === YOUNG_STATUS.NOT_ELIGIBLE && location.pathname !== "/noneligible") return <Redirect to="/noneligible" />;
 
-  if (shouldForceRedirectToEmailValidation(young)) {
+  if (shouldForceRedirectToEmailValidation(young, cohort)) {
     return <Redirect to="/preinscription/email-validation" />;
   }
 
diff --git a/app/src/app.jsx b/app/src/app.jsx
index d894df09dc..4e93904e22 100644
--- a/app/src/app.jsx
+++ b/app/src/app.jsx
@@ -26,6 +26,7 @@ import useAuth from "./services/useAuth";
 
 import PageLoader from "./components/PageLoader";
 import FallbackComponent from "./components/FallBackComponent";
+import store from "./redux/store";
 
 const AccountAlreadyExists = lazy(() => import("./scenes/account/AccountAlreadyExists"));
 const AllEngagements = lazy(() => import("./scenes/all-engagements/index"));
@@ -65,7 +66,8 @@ function App() {
 
       await login(user);
 
-      if (shouldForceRedirectToEmailValidation(user)) {
+      const { cohort } = store.getState().Cohort;
+      if (shouldForceRedirectToEmailValidation(user, cohort)) {
         history.push("/preinscription/email-validation");
       }
     } catch (e) {
diff --git a/app/src/index.jsx b/app/src/index.jsx
index 82280c6388..f7f88bb509 100644
--- a/app/src/index.jsx
+++ b/app/src/index.jsx
@@ -16,10 +16,10 @@ window.addEventListener("vite:preloadError", (event) => {
 });
 
 ReactDOM.createRoot(document.getElementById("root")).render(
-  <React.StrictMode>
-    <Provider store={store}>
-      <App />
-      <ReduxToastr timeOut={5000} transitionIn="fadeIn" transitionOut="fadeOut" />
-    </Provider>
-  </React.StrictMode>,
+  // <React.StrictMode>
+  <Provider store={store}>
+    <App />
+    <ReduxToastr timeOut={5000} transitionIn="fadeIn" transitionOut="fadeOut" />
+  </Provider>,
+  // </React.StrictMode>,
 );
diff --git a/app/src/redux/auth/actions.ts b/app/src/redux/auth/actions.ts
index 555a96428f..335c26c34f 100644
--- a/app/src/redux/auth/actions.ts
+++ b/app/src/redux/auth/actions.ts
@@ -1,12 +1,29 @@
+import { fetchCohort } from "@/utils/cohorts";
 import * as Sentry from "@sentry/react";
+import { Dispatch } from "redux";
 import { YoungType } from "snu-lib";
+import { setCohort } from "../cohort/actions";
 
 export const authActions = {
   SETYOUNG: "SETYOUNG",
 };
 
 export function setYoung(young?: YoungType) {
-  if (young) Sentry.setUser({ id: young._id, email: young.email, username: `${young.firstName} ${young.lastName}` });
-  else Sentry.setUser(null);
-  return { type: authActions.SETYOUNG, young };
+  return async (dispatch: Dispatch, getState: () => any) => {
+    const oldCohortId = getState().Auth.young?.cohortId;
+
+    dispatch({ type: authActions.SETYOUNG, young });
+
+    // Side effects
+    if (young) Sentry.setUser({ id: young._id, email: young.email, username: `${young.firstName} ${young.lastName}` });
+    else Sentry.setUser(null);
+
+    const newCohortId = young?.cohortId;
+    if (newCohortId && oldCohortId !== newCohortId) {
+      const cohort = await fetchCohort(newCohortId);
+      if (!cohort) return;
+      console.log(`Updating stored cohort. New cohort name: ${cohort.name}`);
+      dispatch(setCohort(cohort));
+    }
+  };
 }
diff --git a/app/src/redux/store.ts b/app/src/redux/store.ts
index 5fbd0ad46e..139327cee8 100644
--- a/app/src/redux/store.ts
+++ b/app/src/redux/store.ts
@@ -1,7 +1,9 @@
-import { createStore, combineReducers } from "redux";
+import { createStore, combineReducers, applyMiddleware, compose } from "redux";
 import reducers from "./reducers";
 import * as Sentry from "@sentry/react";
+import thunk from "redux-thunk";
 
 const sentryReduxEnhancer = Sentry.createReduxEnhancer();
+const enhancer = compose(applyMiddleware(thunk), sentryReduxEnhancer);
 
-export default createStore(combineReducers({ ...reducers }), sentryReduxEnhancer);
+export default createStore(combineReducers({ ...reducers }), enhancer);
diff --git a/app/src/scenes/changeSejour/scenes/ChangeSejourMenu.tsx b/app/src/scenes/changeSejour/scenes/ChangeSejourMenu.tsx
index 8f04c1fb5f..9ed1d326d7 100644
--- a/app/src/scenes/changeSejour/scenes/ChangeSejourMenu.tsx
+++ b/app/src/scenes/changeSejour/scenes/ChangeSejourMenu.tsx
@@ -1,6 +1,6 @@
 import React from "react";
 import { Link } from "react-router-dom";
-import useAuth from "@/services/useAuth";
+import useCohort from "@/services/useCohort";
 import { HiArrowRight } from "react-icons/hi";
 import { CohortGroupType, CohortType, getCohortPeriod, getCohortYear } from "snu-lib";
 import plausibleEvent from "@/services/plausible";
@@ -14,7 +14,6 @@ import { capitalizeFirstLetter } from "@/scenes/inscription2023/steps/stepConfir
 import usePermissions from "@/hooks/usePermissions";
 import { useLocation } from "react-router-dom";
 import ErrorNotice from "@/components/ui/alerts/ErrorNotice";
-import useCohort from "@/services/useCohort";
 
 export default function ChangeSejour() {
   const groups = useCohortGroups();
diff --git a/app/src/scenes/home/index.tsx b/app/src/scenes/home/index.tsx
index a9fdc24a06..6dc1d7bf4f 100644
--- a/app/src/scenes/home/index.tsx
+++ b/app/src/scenes/home/index.tsx
@@ -1,7 +1,7 @@
 import React from "react";
 import useDocumentTitle from "../../hooks/useDocumentTitle";
 import { YOUNG_STATUS, hasAccessToReinscription, hasCompletedPhase1, isDoingPhase1 } from "../../utils";
-import { getCohort } from "../../utils/cohorts";
+import useCohort from "@/services/useCohort";
 import InscriptionClosedCLE from "./InscriptionClosedCLE";
 import HomePhase2 from "./HomePhase2";
 import Phase1NotDone from "./Phase1NotDone";
@@ -22,7 +22,7 @@ import useReinscription from "../changeSejour/lib/useReinscription";
 export default function Home() {
   useDocumentTitle("Accueil");
   const { young, isCLE } = useAuth();
-  const cohort = getCohort(young.cohort);
+  const { cohort } = useCohort();
 
   const { data: isReinscriptionOpen, isLoading: isReinscriptionOpenLoading } = useReinscription();
 
@@ -33,14 +33,14 @@ export default function Home() {
   if (young.status === YOUNG_STATUS.REFUSED) return <RefusedV2 />;
 
   // Phase 3
-  if ([YOUNG_STATUS_PHASE3.WAITING_VALIDATION, YOUNG_STATUS_PHASE3.VALIDATED].includes(young.statusPhase3)) {
+  if ([YOUNG_STATUS_PHASE3.WAITING_VALIDATION, YOUNG_STATUS_PHASE3.VALIDATED].includes(young.statusPhase3 as any)) {
     return <Default />;
   }
 
   // Je peux accéder à la Homepage de la Phase 2 si j'ai validé ma phase 1 et que ma cohorte me permet encore de faire la phase 2 :
   const hasMission = young.phase2ApplicationStatus.some((status) => ["VALIDATED", "IN_PROGRESS"].includes(status));
-  const hasEquivalence = [EQUIVALENCE_STATUS.WAITING_CORRECTION, EQUIVALENCE_STATUS.WAITING_VERIFICATION].includes(young.status_equivalence);
-  const hasWithdrawn = [YOUNG_STATUS.WITHDRAWN, YOUNG_STATUS.ABANDONED].includes(young.status);
+  const hasEquivalence = [EQUIVALENCE_STATUS.WAITING_CORRECTION, EQUIVALENCE_STATUS.WAITING_VERIFICATION].includes(young.status_equivalence as any);
+  const hasWithdrawn = [YOUNG_STATUS.WITHDRAWN, YOUNG_STATUS.ABANDONED].includes(young.status as any);
 
   if (hasCompletedPhase1(young)) {
     // les volontaires des première cohortes n'ont plus le droit de faire la phase 2 SAUF si ils l'ont commencé
@@ -65,7 +65,7 @@ export default function Home() {
 
   // Ma phase 1 est en cours, soit en cours d'inscription, soit en plein parcours
   const isCohortInstructionOpen = new Date() < new Date(cohort.instructionEndDate);
-  if (isCLE && [YOUNG_STATUS.WAITING_VALIDATION, YOUNG_STATUS.WAITING_CORRECTION].includes(young.status) && !isCohortInstructionOpen) {
+  if (isCLE && [YOUNG_STATUS.WAITING_VALIDATION, YOUNG_STATUS.WAITING_CORRECTION].includes(young.status as any) && !isCohortInstructionOpen) {
     return <InscriptionClosedCLE />;
   }
 
diff --git a/app/src/scenes/inscription2023/InscriptionClosed.jsx b/app/src/scenes/inscription2023/InscriptionClosed.jsx
index 6e075c8228..ef15a130c3 100644
--- a/app/src/scenes/inscription2023/InscriptionClosed.jsx
+++ b/app/src/scenes/inscription2023/InscriptionClosed.jsx
@@ -1,13 +1,14 @@
 import DSFRContainer from "@/components/dsfr/layout/DSFRContainer";
 import DSFRLayout from "@/components/dsfr/layout/DSFRLayout";
-import { getCohort } from "@/utils/cohorts";
+import useCohort from "@/services/useCohort";
 import { SignupButtons } from "@snu/ds/dsfr";
 import React from "react";
 import { useHistory } from "react-router-dom";
-import { getCohortPeriod, YOUNG_STATUS } from "snu-lib";
+import { YOUNG_STATUS } from "snu-lib";
 
 export default function InscriptionClosed({ young, isCLE }) {
   const history = useHistory();
+  const { cohortDateString } = useCohort();
   const statusWording = (young, isCLE) => {
     if (isCLE) {
       if ([YOUNG_STATUS.REINSCRIPTION, YOUNG_STATUS.IN_PROGRESS].includes(young.status)) {
@@ -29,7 +30,7 @@ export default function InscriptionClosed({ young, isCLE }) {
     <DSFRLayout title={statusTitle(isCLE)}>
       <DSFRContainer title={statusWording(young, isCLE)}>
         {!isCLE ? (
-          <p>Les inscriptions pour le séjour {getCohortPeriod(getCohort(young?.cohort))} sont clôturées. Vous ne pourrez donc pas participer au séjour.</p>
+          <p>Les inscriptions pour le séjour {cohortDateString} sont clôturées. Vous ne pourrez donc pas participer au séjour.</p>
         ) : (
           <p>Les inscriptions dans le cadre des classes engagées ont été clôturées.</p>
         )}
diff --git a/app/src/scenes/inscription2023/index.jsx b/app/src/scenes/inscription2023/index.jsx
index 256075cecd..3becac9063 100644
--- a/app/src/scenes/inscription2023/index.jsx
+++ b/app/src/scenes/inscription2023/index.jsx
@@ -1,5 +1,4 @@
 import React from "react";
-import { useSelector } from "react-redux";
 import { Redirect, useParams } from "react-router-dom";
 import { SentryRoute } from "../../sentry";
 
@@ -20,7 +19,7 @@ import { YOUNG_STATUS, inscriptionCreationOpenForYoungs } from "snu-lib";
 import FutureCohort from "./FutureCohort";
 import InscriptionClosed from "./InscriptionClosed";
 import { knowledgebaseURL } from "../../config";
-import { getCohort } from "@/utils/cohorts";
+import useCohort from "@/services/useCohort";
 import useAuth from "@/services/useAuth";
 import Help from "./components/Help";
 import Stepper from "@/components/dsfr/ui/Stepper";
@@ -103,9 +102,8 @@ const StepCorrection = () => {
 };
 
 export default function Index() {
-  const young = useSelector((state) => state.Auth.young);
-  const { isCLE } = useAuth();
-  const cohort = getCohort(young.cohort);
+  const { young, isCLE } = useAuth();
+  const { cohort } = useCohort();
 
   if (!young) return <Redirect to="/preinscription" />;
   if ([YOUNG_STATUS.IN_PROGRESS, YOUNG_STATUS.REINSCRIPTION].includes(young.status) && young.cohort === "à venir") {
diff --git a/app/src/scenes/inscription2023/steps/stepConfirm.jsx b/app/src/scenes/inscription2023/steps/stepConfirm.jsx
index 3b64954a22..bcfe5e3d9d 100644
--- a/app/src/scenes/inscription2023/steps/stepConfirm.jsx
+++ b/app/src/scenes/inscription2023/steps/stepConfirm.jsx
@@ -1,8 +1,9 @@
 import React from "react";
-import { useDispatch, useSelector } from "react-redux";
+import { useDispatch } from "react-redux";
 import { useHistory, Link } from "react-router-dom";
-import { translate, getCohortPeriod, concatPhoneNumberWithZone } from "snu-lib";
-import { getCohort } from "@/utils/cohorts";
+import { translate, concatPhoneNumberWithZone } from "snu-lib";
+import useAuth from "@/services/useAuth";
+import useCohort from "@/services/useCohort";
 import EditPen from "../../../assets/icons/EditPen";
 import ModalSejour from "../components/ModalSejour";
 import { setYoung } from "../../../redux/auth/actions";
@@ -14,7 +15,8 @@ import DSFRContainer from "@/components/dsfr/layout/DSFRContainer";
 import { SignupButtons } from "@snu/ds/dsfr";
 
 export default function StepConfirm() {
-  const young = useSelector((state) => state.Auth.young);
+  const { young } = useAuth();
+  const { cohortDateString } = useCohort();
   const [modal, setModal] = React.useState({ isOpen: false });
   const [loading, setLoading] = React.useState(false);
   const [error, setError] = React.useState({});
@@ -71,7 +73,7 @@ export default function StepConfirm() {
             <div className="flex items-center justify-between">
               <div className="flex flex-col gap-1">
                 <h1 className="mt-2 text-lg font-bold text-[#161616]">Séjour de cohésion :</h1>
-                <div className="text-lg font-normal text-[#161616]">{capitalizeFirstLetter(getCohortPeriod(getCohort(young?.cohort)))}</div>
+                <div className="text-lg font-normal text-[#161616]">{capitalizeFirstLetter(cohortDateString)}</div>
               </div>
               <button
                 onClick={() => {
diff --git a/app/src/scenes/inscription2023/steps/stepConsentements.jsx b/app/src/scenes/inscription2023/steps/stepConsentements.jsx
index 7c46c9d684..08eb33a6d2 100644
--- a/app/src/scenes/inscription2023/steps/stepConsentements.jsx
+++ b/app/src/scenes/inscription2023/steps/stepConsentements.jsx
@@ -3,7 +3,7 @@ import { useDispatch } from "react-redux";
 import { useHistory } from "react-router-dom";
 import useAuth from "@/services/useAuth";
 import { getCohortPeriod, getCohortYear } from "snu-lib";
-import { getCohort } from "@/utils/cohorts";
+import useCohort from "@/services/useCohort";
 import Error from "../../../components/error";
 import { knowledgebaseURL } from "../../../config";
 import { setYoung } from "../../../redux/auth/actions";
@@ -18,6 +18,7 @@ import Loader from "@/components/Loader";
 
 export default function StepConsentements() {
   const { young, isCLE } = useAuth();
+  const { cohort } = useCohort();
   const history = useHistory();
   const [disabled, setDisabled] = React.useState(true);
   const [loading, setLoading] = React.useState(false);
@@ -61,13 +62,15 @@ export default function StepConsentements() {
 
   if (isLoading) return <Loader />;
 
-  const cohortYear = isCLE ? classe?.schoolYear : getCohortYear(getCohort(young.cohort));
+  const cohortYear = isCLE ? classe?.schoolYear : getCohortYear(cohort);
 
   return (
     <>
       <DSFRContainer
         title="Apporter mon consentement"
-        supportLink={`${knowledgebaseURL}${isCLE ? "/base-de-connaissance/cle-je-minscris-et-donne-mon-consentement" : "/base-de-connaissance/je-minscris-et-donne-mon-consentement"}`}
+        supportLink={`${knowledgebaseURL}${
+          isCLE ? "/base-de-connaissance/cle-je-minscris-et-donne-mon-consentement" : "/base-de-connaissance/je-minscris-et-donne-mon-consentement"
+        }`}
         supportEvent="Phase0/aide inscription - consentement">
         {error?.text && <Error {...error} onClose={() => setError({})} />}
         <div className="mt-4 flex flex-col gap-4 pb-2">
@@ -101,7 +104,7 @@ export default function StepConsentements() {
                       <>M&apos;inscris au séjour de cohésion </>
                     ) : (
                       <>
-                        M&apos;inscris au séjour de cohésion <strong>{getCohortPeriod(getCohort(young.cohort))}</strong> sous réserve de places disponibles{" "}
+                        M&apos;inscris au séjour de cohésion <strong>{getCohortPeriod(young.cohort)}</strong> sous réserve de places disponibles{" "}
                       </>
                     )}
                     et m&apos;engage à en respecter le{" "}
diff --git a/app/src/scenes/phase1/scenes/affected/components/Problem.jsx b/app/src/scenes/phase1/scenes/affected/components/Problem.jsx
index 91994d8b95..cffcd74843 100644
--- a/app/src/scenes/phase1/scenes/affected/components/Problem.jsx
+++ b/app/src/scenes/phase1/scenes/affected/components/Problem.jsx
@@ -1,9 +1,9 @@
 import React from "react";
-import { getCohortPeriod } from "snu-lib";
 import { RiErrorWarningLine } from "react-icons/ri";
-import { getCohort } from "@/utils/cohorts";
+import useCohort from "@/services/useCohort";
 
-export default function Problem({ cohort }) {
+export default function Problem() {
+  const { cohortDateString } = useCohort();
   return (
     <div className="my-12 mx-10 w-full">
       <div className="relative my-0 mb-4 max-w-[80rem] justify-between overflow-hidden rounded-xl bg-gray-50 px-4 py-8 shadow md:mx-auto md:bg-white md:!px-8 lg:!px-16">
@@ -14,12 +14,12 @@ export default function Problem({ cohort }) {
                 <h1 className="text-5xl">Mon séjour de cohésion</h1>
                 <div className="flex flex-row items-center">
                   <h1 className="text-5xl">
-                    <strong>{getCohortPeriod(getCohort(cohort))}</strong>
+                    <strong>{cohortDateString}</strong>
                   </h1>
                 </div>
               </div>
               <div className="mb-4 flex flex-col md:hidden">
-                <h1 className="text-sm text-gray-600 ">Séjour {getCohortPeriod(getCohort(cohort))}</h1>
+                <h1 className="text-sm text-gray-600 ">Séjour {cohortDateString}</h1>
               </div>
             </article>
           </section>
diff --git a/app/src/scenes/phase1/scenes/affected/components/modals/PDRModal.jsx b/app/src/scenes/phase1/scenes/affected/components/modals/PDRModal.jsx
index c840829367..736e11a536 100644
--- a/app/src/scenes/phase1/scenes/affected/components/modals/PDRModal.jsx
+++ b/app/src/scenes/phase1/scenes/affected/components/modals/PDRModal.jsx
@@ -3,18 +3,19 @@ import Modal from "@/components/ui/modals/Modal";
 import { setYoung } from "@/redux/auth/actions";
 import { capture } from "@/sentry";
 import API from "@/services/api";
-import { getCohort } from "@/utils/cohorts";
+import useAuth from "@/services/useAuth";
+import useCohort from "@/services/useCohort";
 import React, { useState } from "react";
-import { useDispatch, useSelector } from "react-redux";
+import { useDispatch } from "react-redux";
 import { toastr } from "react-redux-toastr";
 import MeetingPointChooser from "../MeetingPointChooser";
 import MeetingPointGoAlone from "../MeetingPointGoAlone";
 import { getDepartureDate, getReturnDate } from "snu-lib";
 import MeetingPointConfirmationModal from "../MeetingPointConfirmationModal";
 
-export default function PDRModal({ open, setOpen, meetingPoints, center, session, pdrChoiceExpired }) {
-  const young = useSelector((state) => state.Auth.young);
-  const cohort = getCohort(young.cohort);
+export default function PDRModal({ open, setOpen, meetingPoints, center, session }) {
+  const { young } = useAuth();
+  const { cohort, pdrChoiceExpired } = useCohort();
   const dispatch = useDispatch();
   const [modalMeetingPoint, setModalMeetingPoint] = useState({ isOpen: false, meetingPoint: null });
   const [loading, setLoading] = useState(false);
diff --git a/app/src/scenes/phase1/scenes/affected/components/step/StepPDR.jsx b/app/src/scenes/phase1/scenes/affected/components/step/StepPDR.jsx
index b65ab841da..44469b1905 100644
--- a/app/src/scenes/phase1/scenes/affected/components/step/StepPDR.jsx
+++ b/app/src/scenes/phase1/scenes/affected/components/step/StepPDR.jsx
@@ -5,7 +5,7 @@ import utc from "dayjs/plugin/utc";
 dayjs.extend(utc);
 import { capture } from "../../../../../../sentry";
 import api from "../../../../../../services/api";
-import { getMeetingHour, getReturnHour, isCle } from "snu-lib";
+import { getMeetingHour, getReturnHour } from "snu-lib";
 import { ALONE_ARRIVAL_HOUR, ALONE_DEPARTURE_HOUR } from "../../utils/steps.utils";
 import { StepCard } from "../StepCard";
 import PDRModal from "../modals/PDRModal";
@@ -14,7 +14,7 @@ import useCohort from "@/services/useCohort";
 
 export default function StepPDR({ data: { center, session, meetingPoint, departureDate, returnDate } }) {
   const index = 1;
-  const { young } = useAuth();
+  const { young, isCLE } = useAuth();
   const { pdrChoiceExpired, pdrChoiceLimitDate } = useCohort();
   const [open, setOpen] = useState(false);
   const [meetingPoints, setMeetingPoints] = useState([]);
@@ -46,7 +46,7 @@ export default function StepPDR({ data: { center, session, meetingPoint, departu
     setOpen(!open);
   }
 
-  if (isCle(young)) {
+  if (isCLE) {
     return (
       <StepCard variant="done" index={index}>
         <p className="font-semibold text-sm">Confirmation du point de rendez-vous : vous n'avez rien à faire</p>
@@ -73,7 +73,7 @@ export default function StepPDR({ data: { center, session, meetingPoint, departu
               </div>
             </div>
           </div>
-          {!pdrChoiceExpired(young.cohort) && (
+          {!pdrChoiceExpired && (
             <div>
               <button onClick={handleOpen} className="w-full text-sm border hover:bg-gray-100 py-2 px-4 shadow-sm rounded">
                 Modifier
@@ -81,7 +81,7 @@ export default function StepPDR({ data: { center, session, meetingPoint, departu
             </div>
           )}
         </div>
-        <PDRModal open={open} setOpen={setOpen} meetingPoints={meetingPoints} center={center} session={session} pdrChoiceExpired={pdrChoiceExpired(young.cohort)} />
+        <PDRModal open={open} setOpen={setOpen} meetingPoints={meetingPoints} center={center} session={session} />
       </StepCard>
     );
   }
@@ -104,7 +104,7 @@ export default function StepPDR({ data: { center, session, meetingPoint, departu
               </div>
             </div>
           </div>
-          {!pdrChoiceExpired(young.cohort) && (
+          {!pdrChoiceExpired && (
             <div>
               <button onClick={handleOpen} className="w-full text-sm border hover:bg-gray-100 py-2 px-4 shadow-sm rounded">
                 Modifier
@@ -112,7 +112,7 @@ export default function StepPDR({ data: { center, session, meetingPoint, departu
             </div>
           )}
         </div>
-        <PDRModal open={open} setOpen={setOpen} meetingPoints={meetingPoints} center={center} session={session} pdrChoiceExpired={pdrChoiceExpired(young.cohort)} />
+        <PDRModal open={open} setOpen={setOpen} meetingPoints={meetingPoints} center={center} session={session} />
       </StepCard>
     );
   }
@@ -126,7 +126,7 @@ export default function StepPDR({ data: { center, session, meetingPoint, departu
     );
   }
 
-  if (pdrChoiceExpired(young.cohort)) {
+  if (pdrChoiceExpired) {
     return (
       <StepCard variant="disabled" index={index}>
         <p className="font-semibold text-gray-500">Date de choix dépassée</p>
@@ -141,7 +141,7 @@ export default function StepPDR({ data: { center, session, meetingPoint, departu
         <div>
           <p className="font-semibold leading-tight">Confirmez votre point de rassemblement</p>
           <p className="text-sm mt-2 text-gray-500">
-            À faire avant le <strong>{pdrChoiceLimitDate(young.cohort)}</strong>.
+            À faire avant le <strong>{pdrChoiceLimitDate}</strong>.
           </p>
         </div>
         <div>
@@ -150,7 +150,7 @@ export default function StepPDR({ data: { center, session, meetingPoint, departu
           </button>
         </div>
       </div>
-      <PDRModal open={open} setOpen={setOpen} meetingPoints={meetingPoints} center={center} session={session} pdrChoiceExpired={pdrChoiceExpired(young.cohort)} />
+      <PDRModal open={open} setOpen={setOpen} meetingPoints={meetingPoints} center={center} session={session} />
     </StepCard>
   );
 }
diff --git a/app/src/scenes/phase1/scenes/affected/index.jsx b/app/src/scenes/phase1/scenes/affected/index.jsx
index 9bec98de68..7e3e8c3b82 100644
--- a/app/src/scenes/phase1/scenes/affected/index.jsx
+++ b/app/src/scenes/phase1/scenes/affected/index.jsx
@@ -2,7 +2,7 @@ import React, { useEffect, useState } from "react";
 import { toastr } from "react-redux-toastr";
 import { capture } from "@/sentry";
 import { isCle, transportDatesToString, youngCanChangeSession, getDepartureDate, getReturnDate } from "snu-lib";
-import { getCohort } from "../../../../utils/cohorts";
+import useCohort from "@/services/useCohort";
 import api from "../../../../services/api";
 import { AlertBoxInformation } from "../../../../components/Content";
 import ChangeStayLink from "../../components/ChangeStayLink";
@@ -25,7 +25,7 @@ export default function Affected() {
   const [showInfoMessage, setShowInfoMessage] = useState(false);
   const [loading, setLoading] = useState(true);
 
-  const cohort = getCohort(young.cohort);
+  const { cohort } = useCohort();
   const departureDate = getDepartureDate(young, session, cohort, meetingPoint);
   const returnDate = getReturnDate(young, session, cohort, meetingPoint);
   const data = { center, meetingPoint, session, departureDate, returnDate };
diff --git a/app/src/scenes/phase1/waitingAffectation.jsx b/app/src/scenes/phase1/waitingAffectation.jsx
index eb4a80bd43..e2a8ef014b 100644
--- a/app/src/scenes/phase1/waitingAffectation.jsx
+++ b/app/src/scenes/phase1/waitingAffectation.jsx
@@ -1,5 +1,5 @@
 import React from "react";
-import { getCohortPeriod, youngCanChangeSession } from "snu-lib";
+import { youngCanChangeSession } from "snu-lib";
 import { Link } from "react-router-dom";
 import hero2 from "../../assets/hero-2.png";
 import heroBanner from "../../assets/hero-banner.png";
@@ -15,16 +15,14 @@ import Files from "./Files";
 import ButtonExternalLinkPrimary from "../../components/ui/buttons/ButtonExternalLinkPrimary";
 import useAuth from "@/services/useAuth";
 import { RiInformationFill } from "react-icons/ri";
-import { getCohort } from "@/utils/cohorts";
+import useCohort from "@/services/useCohort";
 import plausibleEvent from "@/services/plausible";
 
 export default function WaitingAffectation() {
   const { young, isCLE } = useAuth();
+  const { cohortDateString } = useCohort();
   const shouldShowChangeStayLink = !isCLE && youngCanChangeSession(young);
 
-  const cohort = getCohort(young.cohort);
-  const cohortDate = getCohortPeriod(cohort);
-
   function handleClick() {
     plausibleEvent("CLE attente affectation - desistement");
   }
@@ -39,7 +37,7 @@ export default function WaitingAffectation() {
           <div className="mb-10 max-w-3xl">
             <header className="md:mt-12 mb-12">
               <h1 className="text-[44px] mt-0 mb-1">Mon séjour de cohésion</h1>
-              <h2 className="text-[44px] mt-0 mb-3 font-bold">{cohortDate}</h2>
+              <h2 className="text-[44px] mt-0 mb-3 font-bold">{cohortDateString}</h2>
               {shouldShowChangeStayLink && <ChangeStayLink />}
             </header>
             <div className="flex my-4 items-center gap-4 rounded-xl border-[1px] border-gray-200 bg-white p-3">
diff --git a/app/src/scenes/phase1/waitingList.jsx b/app/src/scenes/phase1/waitingList.jsx
index 95d018142a..cc1c813a26 100644
--- a/app/src/scenes/phase1/waitingList.jsx
+++ b/app/src/scenes/phase1/waitingList.jsx
@@ -1,15 +1,16 @@
 import React from "react";
 import { Link } from "react-router-dom";
-import { getCohortPeriod, youngCanChangeSession } from "snu-lib";
+import { youngCanChangeSession } from "snu-lib";
 import clock from "../../assets/clock.svg";
 import edit from "../../assets/editIcon.svg";
 import hero from "../../assets/hero.png";
 import { knowledgebaseURL } from "../../config";
 import Container from "./components/Container";
 import Files from "./Files";
-import { getCohort } from "@/utils/cohorts";
+import useCohort from "@/services/useCohort";
 
 export default function WaitingList({ young }) {
+  const { cohortDateString } = useCohort();
   return (
     <>
       <Container>
@@ -19,7 +20,7 @@ export default function WaitingList({ young }) {
               Mon séjour de cohésion
               <br />
               <strong className="flex items-center">
-                {getCohortPeriod(getCohort(young.cohort))}{" "}
+                {cohortDateString}{" "}
                 {youngCanChangeSession(young) ? (
                   <Link to="/changer-de-sejour">
                     <img src={edit} alt="edit icon" className="ml-2 h-9 w-9 hover:h-10 hover:w-10 hover:cursor-pointer" />
diff --git a/app/src/services/useAuth.ts b/app/src/services/useAuth.ts
index 905773c3e2..3de74aab2f 100644
--- a/app/src/services/useAuth.ts
+++ b/app/src/services/useAuth.ts
@@ -4,10 +4,8 @@ import { setYoung } from "../redux/auth/actions";
 import { toastr } from "react-redux-toastr";
 import { logoutYoung } from "./young.service";
 import { YOUNG_SOURCE, YoungType } from "snu-lib";
-import { fetchCohort } from "@/utils/cohorts";
 import { displaySignupToast } from "@/utils";
 import { AuthState } from "@/redux/auth/reducer";
-import { setCohort } from "@/redux/cohort/actions";
 
 export const useAuth = () => {
   const dispatch = useDispatch();
@@ -26,11 +24,7 @@ export const useAuth = () => {
 
   const login = async (user?: YoungType) => {
     if (!user) return history.push("/auth");
-    dispatch(setYoung(user));
-    const cohort = await fetchCohort(user.cohortId);
-    if (cohort) {
-      dispatch(setCohort(cohort));
-    }
+    await dispatch(setYoung(user));
     displaySignupToast(user);
   };
 
diff --git a/app/src/services/useCohort.ts b/app/src/services/useCohort.ts
index 4a7e0e0d1a..93c6f056fa 100644
--- a/app/src/services/useCohort.ts
+++ b/app/src/services/useCohort.ts
@@ -2,9 +2,10 @@ import { CohortState } from "@/redux/cohort/reducer";
 import { pdrChoiceExpired, pdrChoiceLimitDate } from "@/scenes/phase1/scenes/affected/utils/steps.utils";
 import { cohortAssignmentAnnouncementsIsOpenForYoung, getMeetingPointChoiceLimitDateForCohort, isCohortDone, isCohortNeedJdm } from "@/utils/cohorts";
 import { useSelector } from "react-redux";
+import { getCohortPeriod } from "snu-lib";
 
 export default function useCohort() {
-  const cohort = useSelector((state: CohortState) => state.Cohort.cohort);
+  const { cohort } = useSelector((state: CohortState) => state.Cohort);
   return {
     cohort,
     cohortAssignmentAnnouncementsIsOpenForYoung: cohortAssignmentAnnouncementsIsOpenForYoung(cohort),
@@ -13,5 +14,6 @@ export default function useCohort() {
     isCohortNeedJdm: isCohortNeedJdm(cohort),
     pdrChoiceLimitDate: pdrChoiceLimitDate(cohort),
     pdrChoiceExpired: pdrChoiceExpired(cohort),
+    cohortDateString: getCohortPeriod(cohort) as string,
   };
 }
diff --git a/app/src/utils/cohorts.ts b/app/src/utils/cohorts.ts
index 22cfc01deb..ee25d5257b 100644
--- a/app/src/utils/cohorts.ts
+++ b/app/src/utils/cohorts.ts
@@ -39,9 +39,13 @@ export const canYoungResumePhase1 = (y: YoungType): boolean => {
 };
 
 export async function fetchCohort(cohortId: string): Promise<CohortType> {
-  const res = await fetch(`${apiURL}/cohort/${cohortId}/public`);
-  if (!res.ok) {
-    throw new Error("Unable to fetch cohort");
-  }
-  return res.json();
+  return fetch(`${apiURL}/cohort/${cohortId}/public`)
+    .then((res) => res.json())
+    .catch((error) => {
+      throw new Error(error);
+    })
+    .then((res) => {
+      if (!res.ok) throw new Error("Unable to fetch cohort");
+      return res.data;
+    });
 }
diff --git a/app/src/utils/index.js b/app/src/utils/index.js
index 0ce458fadf..389e7cdea2 100644
--- a/app/src/utils/index.js
+++ b/app/src/utils/index.js
@@ -2,9 +2,10 @@ import PasswordValidator from "password-validator";
 import { YOUNG_STATUS, YOUNG_STATUS_PHASE1, YOUNG_STATUS_PHASE2, YOUNG_STATUS_PHASE3, REGLEMENT_INTERIEUR_VERSION, isCohortTooOld, EQUIVALENCE_STATUS } from "snu-lib";
 export * from "snu-lib";
 import slugify from "slugify";
-import { getCohort, isCohortDone } from "./cohorts";
+import { isCohortDone } from "./cohorts";
 import { toastr } from "react-redux-toastr";
 import { INSCRIPTION_STEPS, REINSCRIPTION_STEPS } from "./navigation";
+import store from "@/redux/store";
 
 function addOneDay(date) {
   const newDate = new Date(date);
@@ -104,7 +105,7 @@ export function hasAccessToPhase2(young) {
   const userIsDoingAMission = young.phase2ApplicationStatus.some((status) => ["VALIDATED", "IN_PROGRESS"].includes(status));
   const hasEquivalence = [EQUIVALENCE_STATUS.WAITING_CORRECTION, EQUIVALENCE_STATUS.WAITING_VERIFICATION].includes(young.status_equivalence);
 
-  const cohort = getCohort(young.cohort);
+  const { cohort } = store.getState().Cohort;
   if (isCohortTooOld(cohort) && !userIsDoingAMission && !hasEquivalence) {
     return false;
   }
diff --git a/app/src/utils/navigation.js b/app/src/utils/navigation.js
index d68d43d040..e7780defb2 100644
--- a/app/src/utils/navigation.js
+++ b/app/src/utils/navigation.js
@@ -1,5 +1,4 @@
 import { FEATURES_NAME, isFeatureEnabled, YOUNG_SOURCE, YOUNG_STATUS } from "snu-lib";
-import { getCohort } from "./cohorts";
 import { environment } from "@/config";
 
 export const INSCRIPTION_STEPS = {
@@ -264,8 +263,7 @@ export const redirectToCorrection = (young, field) => {
   return correction ? correction.redirect : "/";
 };
 
-export function shouldForceRedirectToEmailValidation(user) {
-  const cohort = getCohort(user.cohort);
+export function shouldForceRedirectToEmailValidation(user, cohort) {
   const isEmailValidationEnabled = isFeatureEnabled(FEATURES_NAME.EMAIL_VALIDATION, undefined, environment);
   const shouldUserValidateEmail = user.status === YOUNG_STATUS.IN_PROGRESS && user.emailVerified === "false" && new Date() < new Date(cohort.inscriptionModificationEndDate);
   const pathname = window.location.pathname;
diff --git a/package-lock.json b/package-lock.json
index dc0b5a97a2..a97a748f1d 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1738,6 +1738,7 @@
         "react-tooltip": "^4.5.1",
         "reactstrap": "8.10.1",
         "redux": "4.2.1",
+        "redux-thunk": "^2.4.0",
         "regenerator-runtime": "0.13.9",
         "remark-gfm": "^4.0.0",
         "slugify": "^1.6.5",
@@ -23107,6 +23108,15 @@
         "@babel/runtime": "^7.9.2"
       }
     },
+    "node_modules/redux-thunk": {
+      "version": "2.4.0",
+      "resolved": "https://registry.npmjs.org/redux-thunk/-/redux-thunk-2.4.0.tgz",
+      "integrity": "sha512-/y6ZKQNU/0u8Bm7ROLq9Pt/7lU93cT0IucYMrubo89ENjxPa7i8pqLKu6V4X7/TvYovQ6x01unTeyeZ9lgXiTA==",
+      "license": "MIT",
+      "peerDependencies": {
+        "redux": "^4"
+      }
+    },
     "node_modules/reflect-metadata": {
       "version": "0.2.2",
       "resolved": "https://registry.npmjs.org/reflect-metadata/-/reflect-metadata-0.2.2.tgz",