Oh, I see. My bad, I had gotten back from a strenuous 2-hour couch lifting session and was tired and wasn't focusing last night.
I actually also did that as well, used the shed as a sort of foyer for the rest of the house. I had this same problem last year, but I caught the issue early and reloaded to rebuild it a few time to figure out why Mirel was sleeping on the floor in the shed and not in her new room. But, yeah, I agree it did seem to break something in Mirel's pathing, but I still think it's because of the naming of isolated buildings not being the same name as the shed. Making them the same worked for me, but I can imagine you do not want to redo all the floors to work around the effect of the issue.
What specifically about the update do you think is causing the issue if you think it's not the named isolated building trying to merge with the shed? You think it was something else in the update?