Is it school nursery? Or private day care? Or childcare nursery said we could drop off DS1 any time they were open if I was in labour, they WOULD find a space for him.
We too had our nearest childcare down the M1, and despite phoning my Mum on the first contraction (at 4.30am.....), Childcare, paramedics and baby all turned up within 90seconds of each other at 7am. I think DH had the worst of it, dealing with ambulance control, a toddler, and a wife in labour.
I think if your partner is doing the childcare, he won't be much support as a birthing partner, as his mind will be on other things.
It's another money solution, but have you considered a doula to be your birthing partner, and then your partner can look after your daughter until someone can arrive, and then he can come and support you? It may still mean he misses the birth.
Unless your prone to fast labours (10 total labour, 3 hrs active labour with first, 2.5 hrs first contraction to baby with second here), I think you should have time, so long as you are prepared to ring at whatever time things kick off.