I have been having this happen in my 1.16.40 game. BDS hosted on my machine.
Sometimes villagers go missing, sometimes they change professions.
This last time it happened to three villagers at the same time - all were enchanters, in the same room with three lecterns and all traded up at least two levels.
All kept their levels. One stayed an enchanter, but his books changed.
And the profession only changed once - after that, it "stuck". I've destroyed the lecterns and replaced them, but the villagers are not changing back.
Earl Brown
I have been having this happen in my 1.16.40 game. BDS hosted on my machine.
Sometimes villagers go missing, sometimes they change professions.
This last time it happened to three villagers at the same time - all were enchanters, in the same room with three lecterns and all traded up at least two levels.
All kept their levels. One stayed an enchanter, but his books changed.
And the profession only changed once - after that, it "stuck". I've destroyed the lecterns and replaced them, but the villagers are not changing back.
All were recently healed from being zombies.