However, increased size in aircraft on EI services on Dublin London could release BA's own slots (from the Dublin route) that could be deployed onto their own long haul routes.
Or Aer Lingus', remember when it was assumed BA would drop DUB after getting BMI and just codeshare with EI? In a more commercial environment, the current SNN-LHR just doesn't work, it's the EI equivalent of BA's LHR-LBA. The first inbound to London is useless for point to point. Depending on how much feed BA get from ORK/SNN/BHD with EI, they might be better of at LGW....in commercial terms. They are of course knee deep in local politics.
However an IAG owned Aer lingus would surely be a more aggresive entiity at MAN, even to the extent of feeding American's exisiting MAN operation as overflow from DUB.