I ran into this issue today. Instead of just being able to move the graduated sims out of the household as per usual, it moved all of my sims to that slot, while also being able to transfer some of the same sims to that slot. So, now I have two of every sim in that one slot to move out of the household and won't let me move them around. I saved and exited the game, hoping it would fix the issue, but when I returned to the game, it moved my game all the way back to Thursday instead of Saturday. My sims had already previously enrolled for a new term on Friday, and then moved all the way up to the graduation event on Saturday, then was getting ready to move my graduated sims out of the household which is when the issue occurred. It saved all of their enrollment progress, but now it's wacky because it's on Thursday now instead of Saturday like it should be.