Ausgirl is right - for CCB and CCR, the childcare can backdate up to 28 days from the date of grant of CCB. so if it was all granted right back and it was only missing information for DD2, IN THEORY, they can go and have the CCB paid to them right back - however, most won't. they will back date 28 days from when you provide the information (in terms of their billing) and then submit usage (but not claim ccb/ccr) going back to the date of grant and the ccb/ccr for that period will be paid at tax time. if your child started in care before you had ccb granted, you will need to do a lump sum claim at tax time from the date your started child care til the date ccb was granted for that child

the same will likely happen with DD1 and her immunisation cancellation/reinstatement. if it's been more than a month, the child care may not go right back to when it was reinstated. mostly because, for them, it's messy to try and claim back there and fix up/credit your bill going forward. as long as they have put in the usage statements each week (you can check this online) it will be sorted and paid at tax time.