FYI, that 10 emeralds for 1 nametag villagerĀ didĀ remain at master level, but every other one went back to novice. Every one of them changed their trades though, and only 1 of 12 had no trading exp and could have their trades reset by replacing their workstation.
It would have been less of a slap in the face if they all just vanished, instead of them changing to having garbage trades that I can't fix without first removing and then replacing them.
As a follow-up, I have one cleric and many librarians, and the cleric did keep the 1 emerald for 1 exp bottle trade. Not sure if that helps as the sample size is pretty askew between the two types. Since I'll be replacing the librarians anyways, I'll update this ticket with any meaningful updates if I come across any.
Until then, I have a lot of librarians to "take care of" š¬