Don't worry too much about the sleeping arrangements - even if your kids like having their own room. Siblings need closeness now especially. Sharing a room will help with that. You can always spin it as it being much cozier to share. RAI
This post left me worrying. My W is moving out 1st October to her new place and one of advantages of this new place she sold to the kids is that each one of them will have his own room. Now that I think about it, they have never slept in a separate bedroom. Half an hour ago I tucked in S7 and he was fighting the sleep because his brother is downstairs sleeping with the neighbours and the mother was also downstairs telling the landlord she is moving out. He kept asking for them, especially for the mother.
Me43 W39 M 12y,T 15y S09,S07 Bomb Jun14 Sleeping separately Jan/Mar15 Share bed Mar/May15 Reconcile Jun15 Aug15 W sais D will happen D told to kids Sept15 W moved out with kids 01 October15