After more sleuthing it appears that the person who owns the land may of died several years ago. But it hasn't passed onto anyone else it seems. A friend has a local planning and buildings regs guy who is going to look a bit deeper for us.
The land was being used to store building materials and such, so I'm guessing the locals didn't like the extra disturbance that brought.
The site itself would be useless for a housing developer because of the shape of it, where it is and other inconveniences. Perfect for a small self build though.