The buk of the "mid haul" flights are those acquired with the British Mediterranean operation in 2007. This had been operated as a BA franchise for the previous 10 years, and as far as the passengers were concerned was not discernable from the main BA operation.
I believe BA had first refusal on the business when it was offered for sale, which would just have bee a straight integration of what de facto already existed. Why did BA walk away from this and thus BMI managed to get into this market ? Why are things different now such that BA would want these previously unwanted routes back ?