Nursery No 1 is not within its rights to charge fees for a service it isn't providing, and a quick call to one of the national newspapers would have this behaviour brought to the attention of the government daily briefing very quickly. Moreover, if this nursery wishes to keep afloat and retain its staff it has the government furlough scheme to help it, and let's face it, nurseries are money-making rackets for the owners as they pay their staff a pittance and charge exorbitant fees. Most of their owners are living luxurious lives. I have seen this for years as I know several.
Your DD is very courageous and altruistic returning to work after maternity leave. She's a frontline worker whom Nursery No 1 is trying to 'do over'. The owners/management need to be held to account for this. It's an issue that needs raising in public for quick answers and a call to a newspaper journalist would be the thing to do.
Frankly,