Nursery fees

270+6.25 276.25 *52 (if they charge for full 52 weeks in a year) / 12 months is 1191.1 per month.
Isn’t your weekly rate including the funded hours? You can ask the nursery to give you a breakdown of costs as you’d need to be sure it’s affordable before they invoice.
What is the 80% about?

Are you referencing the tax free childcare (the government top up in your childcare account) when you say 80%? If so, yes you should still get it, I get both.
So your weekly bill is £295. The 15 hours is only over 38 weeks of the year, you pay full for the other weeks. Assuming your LO will be going to nursery all year, some nurseries do have the option to split it. For example, we split it over the whole 49 weeks that our nursery is open, which means we get 9 funded hours every week.

I would ask your nursery tbh, we get our free funding which is worked out over 38 weeks but for every funded hour it’s £2 plus £5 for lunch. I know a lot of nursery’s are introducing these fees.x

Our nursery sent a fee sheet which just said exactly the cost per month broken down by child age, with or without funded hours, and the number of days attended per week

They have to know the cost to be able to bill you anyway so it’s worth asking the nursery if they can tell you!