It just depends on how much Manchester will put up with and the lack of work on the GH side - Aegean has joined Star Alliance group and that is how it got slots into LHR. Apparently from winter season onwards.
Manchester will not sustain under-performing stations, or in this case parts of station, they knows whats going on, and GH have been on a knife-edge for a while. The departure of Aegean, may well be the final push and be sent to the guillotine[apologies for poor spelling].