I experienced this too. I tried to submit 45 minutes before the deadline and got this error. I kept refreshing and trying to resubmit until finally giving up around 1 am, almost an hour after the deadline. Oh well. :/
I had this same problem. You don't have to move out the whole household, just the baby. Move the baby into another household, then go back to the original household and replace the bassinet with the one you want and then move the baby back in.
New Chapters: Chapter 7.68 - The Result Chapter 7.69 - Winter Ball Chapter 7.70 - Moving In Chapter 7.71 - Love Day Chapter 7.72 - Endorsement Chapter 7.73 - Mission Accepted I'm so bad at updating this thread! :D