Yeah that's what I was thinking but not very clear about. It would have to migrate under the board quite a bit wouldn't it?
(in Michael Palin voice) Are you suggesting that glue is migratory?
Hard to tell, could have happened that way, or it could be that too much moisture had already gotten in after the glue line was broken (and before regluing) and caused the neck to swell when more glue was applied.