I appreciate T-URBO efforts to ressolve the operations in this area. I suggest we give him a few days to let us know abit more of his enquiries

I checked Skyvector. I noticed that Airspace boundaries for Tower seem to be rather clear. I believe the best approach here would be if everyone chooses an airport an offer systematically Tower (with lateral and vertical airspace restrictions as shown in Skyvector and/or other charts), and someone with more experience offers the high-altitude control (Maybe it is London_Center?)
If this is the case, I'd give my confidence vote to Elgaton who has a very amazing record with us managing crazyness in the Festival

Finally, in more isolated positions the Controllers operate either as centers or Approach (example, Legoboy in Belfast and IH-COL in Edinburgh)
IH-COL