It's not that LHR is not working and that LGW will be better, it's that London isn't working for them. Too many more competitive options, this service is a mix of vanity and political, but worse than that, the B77W was just WAAAAY too big. I doubt the change to the A339 will generate a profit but it may scale back the losses a tad. Moving back to LGW wouldn't help matters one little bit, it may be operationally somewhat cheaper but that's not enough.