Settings are not allowed to dictate how many funded sessions parents take up. Funded sessions must be completely free, but it is up to the setting to decide which hours in a day they offer the funded hours for.
The setting get funding for your child to attend and if she/he doesn't without good reason then the local authority can claim it back. That is why the preschool might seem a bit funny by you not bringing her. I hope that helps?
It's up to the provider, if they want to make certain rules that's up to them. Sometimes it's to avoid lunch cover, so the first set of children get picked up at one time and then the next lot arrive a bit later. Other places don't worry, you can arrange whatever suits with the spaces they have. My DD will be doing 9-3 Mon and Tues, and 9-11.30 Weds once she gets funding, but we could have had mornings, afternoons, or a mix. They close at 11.30 on a weds which is a shame.
Is it basically up to the provider to decide how they work this? My most local council run nursery school offers morning or afternoon sessions, so 5 x 3 hours. However, they are attached to a unit that provides daycare as well. DS is currently in the daycare three full days. If/when he gets (just turned three) to this side of the unit should I be able to expect 3 x 5 sessions and so get his 15 hours over three days? Other local privately run units offer this.
Also, (this is turning into an essay) I got the impression that they would frown upon it if DS got a place but wasn't there for the 3 hr sessions on days when he doesn't need to go. Would I actually be obliged to send him?
I hope this makes sense, I am quite confused myself!