It takes ages. Also, as we’re in the new tax year, they will likely say you’re only entitled to the basic £25 ish until you pay any outstanding class 2 contributions for the new tax year (e.g. I owed just over £46). They don’t tell you about this for weeks, and then once you’ve paid it they don’t give you the money for weeks. I applied for my pay back in June and I’m only getting my first FULL payment tomorrow! Same thing with both of my children x
I got a response within 19 days, and I applied really late 2 months after birth. So, be hopeful they respond within 4 weeks or less
They will likely take the full 4 weeks to make any contact. As for how soon after that the payment will be processed I’m not sure as I did mine in advance. They will pay you any backdated money though