I don't know, but might this not be just a result of fitting GLA/EDI/BFS-STN into the gaps to LTN.
It doesn't seem to make a lot of sense having flights to STN and LTN and LGW going at the same time. I know that not all pax want to go into central London, but in many ways it is relatively straight forward by train and coach from all 3 of these EZY airports?