Puzzle about the mechanism

[Refrain-123]

Hi Mike,
Thx for your proposal Stamp in the Bitcoin ecosystem, that's sth really different from what I've known about Ordi.
I have read some materials about the Stamps protocol, and I think by far I figure out the mint mechanism about it. But I still got one queation, how does the "transfer" work between buyers.
Before the update to "key burn", when the creator inputs his key, he could unspent the UTXO which contains the art, that may not be what we want. So I understand the importance of introducing "key burn". But since it's unspendable, this UTXO is left permanently in UTXO set, how could we tell the owner of it or transfer it to someone else?
Thx for your reply