Something shady going on.
2-#### is the international code for aircraft registered in the Isle of Man.
Most of these aircraft seem to be owned by people organisations in the Channel Islands.
Theoretically they are civilian but they show up on the military scanner.
Keep trying to discover more about them but not having much luck.
One of the aircraft is operated with a working capital of £100 per year.
Post any thing you can find. It's been difficult planefagging and digging at the same time but with more hands it should be easier.