The security relief at Buck House would have to be rescheduled. Remember KCII doesn't actually live there.
So for Harry to stay, they would need to put a protection squad on nights, plus catering and house staff. Harry is supposed to arrive tomorrow. Police rotas will have been fixed for the week, resources allocated.
Are you expecting the Met to call in a corridor officer plus wider protection team and driver from rest days or give overtime at 24 hours notice? That's absurd.
If Harry wanted to stay, he should have accepted a week ago when he had the chance.
Harry does love to cause a drama and then whine doesn't he ! Anyone normal with manners would have accepted KCII's kind offer a week ago.