I would assume (although I was always told not to assume anything) that competition from Ryanair on the route must have a lot to do with it. Monarch have cut back a lot of scheduled flights this coming winter from numerous airports. One example - no flights to Mahon from Luton and much reduced to Malaga and Gibraltar (wonder about the latter as loads have been very good lately but maybe the yield has been poor and that is what really matters). Hope this helps.