yeah i get that for a lot of them. i guess a random example i could think of (theoretically to illustrate, i don't have an actual example on hand) would be something like EWR-NRT (UA79) and SFO-NRT (UA837). UA79 i flew a lot and is still operated by the two cabin 772 i fly frequently, and UA837 is flown by the three cabin 744 i've tried once.

all the flight information that was stored in CO's old shares instance about UA79 was always structured in the beginning to work (well... i use the term "work" liberally here). copying it over to the new UA shares should be (relatively) easy.

then all the information about UA937 in apollo has to be translated and moved into whatever format shares wants it. same with the old MP information and pre-3/3 reservations. so if the information about that flight was botched to begin with, it would make sense that all the PMUA stuff would cause more issues.

but to your point, maybe that's what it will take for things to be less painful, where in a year all the screwups from the botched migration are flushed out with purely post-3/3 reservations?