As a holding company IAG may think they can turn round Flybe into Profitable operation under their tutelage, they haven’t actually merged any of their businesses todate , all being stand alone yes even Iberia and British Airways report independently having their own performance targets and have little to no synergies with Vueling or AerLingus in reality.
Aer Lingus aren’t a Oneworld carrier indeed continue to partner with a Star alliance carrier across the Atlantic (United) over American !
The strengths in IAG are very tight corporate and financial management of their brands and very high expectations where numbers are set.
These strengths are what might just turn round the brand that is Flybe imho.
Without doubt they would be quite roughless in pruning the branches of the tree and I believe they would significantly reduce the bases currently operating to arround perhaps just three Edinburgh, Belfast and one of either Manchester or Birmingham.