CircularTrapezoid47: Hello!
You are correct on everything, LB chooses a "canonical" release automatically (the earliest album release containing the recording).
There is currently no way to re-link it to a specific release, however this is a hotly requested feature so we are already working on that (amongst 50 other projects :D).
It is not an easy one to implement as it ends up touching a lot of different parts of the codebase, so don't expect it to be resolved straight away.
If you want to follow progress on it, the ticket is https://tickets.metabrainz.org/browse/LB-1399