GP's are not a part of the NHS, they are contractors. Anybody who wishes to do so can apply to set up a GP service and be paid for it by the NHS if the place they offer to set it up needs GP services. As with any other contractor, they have to comply with the contract that is set out by the commissioning body. oh and PS GP's have never been part of the NHS, they have always been contractors.
And just to remind folk, it was the Labour party who set up the money losing PFI system which the NHS is still paying for, and the Labour party who allowed GP services to opt out of providing OOH services without correspondingly reducing what GP practices were paid. I was there in the NHS at the time and if I told you what was said then I too would be banned from GN