Since planning their fleet renewal, BA have picked up a lot more LHR slots from BMI. I suspect retirements will be much slower, as new or displaced aircraft are used to open up more longhaul routes (with a corresponding reduction in Domestic and Euro flying, and these airbus (former BMI) moved to LGW).

At least that is what I would do, on the hypothesis that a longhaul route contributes more profit than a shorthaul one.