oh yes, I do like that if you talk to some NPCs before their sidequests you actually get some hints about them that help a bit during some sidequests.
Like, if you talk to an NPC called Suriella she mentions in a weird way how the lady in front of her was talking about her home on Planet Earth and thenduring a sidequest you find out that she was a Definian spy all along
It's cute and also makes me want to speak to everyone after almost each chapter to see if their dialogue has changed.
I'm never going to finish this game T_T
NPC dialogue and location may change after any chapter, after any sidequest they may be even tangentially related to, or after any new alien races move in. Other than Kiseki I don't think there's any JRPGs on the market that I've played that handle NPC development so well.