Clarification on claiming 30 hours childcare

[Lostsoul123]

Hi there!
My son turned 3 in September and will be starting at a private nursery from the January term when he is eligable to recieve his funded 30 hours. I applied for his gov code for the funded 30 hours on the 22nd October.
I filled out a parent declaration form with the code on yesterday which the nursery advised me yesterday they will send on to the local authority ASAP. Just a couple of questions about this- is there a deadline the nursery needs to meet regarding this? Not sure if it's paperwork that gets sent off? And how long it roughly takes for the local authority to approve this? I'm just anxious about not meeting a deadline as it would be a massive blow to us to not recieve the hours.
Plus, if he starts on 8th Jan when do I renew his code? The nursery advised that I could renew now but I have had other people telling me this is not possible until nearer the time- plus I don't want a renewal now to look as if I'm applying late despite applying earlier if this makes sense! I realise I a probably am massively overthinking this but would appreciate some advice please?

As far as I understood the nursery uses the code around the time of doing the invoice for the allotted time.
We thought it was some kind of super official forms and manager almost laughed. I think the main thing is they have the number before the hours start. My daughter started her 30 free hours in September and we filled in the form and I don't know magic happened and our bills dropped. We now pay £12 for 3 days and the normal rate on the 4th day. When we took her on holiday we had a form to fill in to say why she wasn't in that week.