As far as I know the Office will be kept. Budget constraints are more the likely going to force their hand. The office set is just in a small room shared with Newsround. I can't see them going back to a proper good sized studio. Budgets is why they pulled out of TC9 & TC10 originally.
Caught this purely by chance channel surfing, but according to Ed and Oucho, their replacements for CBBC continuity are going to be Sam and Mark. Oucho thinks they're going to be rubbish.