Flashing two files (code and SoftDevice) using offsets

[ryanmillerwork]

I'm trying to flash an nRF52840 with code for the b-parasite project (https://github.com/rbaron/b-parasite/wiki/How-to-Program). That project requires the SoftDevice protocol stack to be copied as well as the custom program code. I assume I need to use offsets for this, but it's unclear to me how to know what the offsets should be. Any suggestions? Thanks.