I would have done, too ;o)
The other thing I thought of - Roger's got his own camper that's parked in the car park. What do they do about that? We've got to think up ways to make this bloody hard for them - and also, if the Uni dig decides (as they have done) to leave security on site for the digs, they'll be contravening NT's rules too. And what about that patch of private land that belongs to the vicar - does that come under the ruling too - it doesn't belong to the National Trust?