MUFC, right too, BUT EDI is now full to the brim with low-cost operators, and only the fittest will survive. It aint gonna be JET2 and certainly not GSM...
Don't forget Jet2 have the highly profitable Royal Mail contract at EDI, which requires 2-3 based aircraft to operate it at night alone. Before they started pax ops those aircraft used to sit on the cargo apron doing nothing all day.
They've been doing a good job of filling in the gaps in EDI's route network that other operators have been ignoring eg PRG. Yet unfortunately they always seem to be the ones who get bullied off a route when the big guys sit up and take notice of how well Jet2 are doing on the route eg EZY to Milan, Ryanair to PSA and MRS.
As for GSM, I think they'd now be better concentrating on their flight+hotel packages that they do that the likes of FR don't offer as that's the only way they can take the fight to them on routes like ALC, AGP and PMI unfortunately. Otherwise they're going to be killed. They should also be looking to the likes of Cyprus, Greece, more Egypt and Canaries, ORLANDO!!! for expansion. The sort of places where due to sector lengths EZY and FR and very unlikely to venture.