Also happens with vanilla villagers. For MCA, the places that you registered will eventually be reset and the villager will wander and swap beds, change profession, etc...

Yeah, quick update from last time, I checked out the blueprint but it said that their house was switched from the original one, maybe because of chunk reset or something? I don't know, my villagers had always sleep all over what beds they can see in my town.

Workplace have vanilla behavior, they should only reset if you destroy the working block.
Hangout is not implemented yet.
Regarding home: do they also swap buildings? (For the mca villagers, vanilla do not have a really permanent concept of a home) If you do not explicitly define a bed they may swap beds within the same building whoever comes first.

Nope, the villager even came an lay in the bed, but later she decided to just sleep in a completely new home, I have about 25 villagers in my village and this happens quite frequently.

Do the blueprints home assignment match the location they sleep?

Havent mess with the blueprint that much, i will double check this.

Will become irrelevant in upcoming versions