Going East all their former markets from MAN, GLA, EDI, NCL are now served at multiple frequency by QR, Etihad, EK, THY etc.
That's an act of geography, all the above carriers can offer one stop to an awful lot more going that way than BA. Of course the same case does not stack up going South or West which is why there's still a BA offering into the long haul hub at T5 and why the STAR Alliance airlines are not happy at losing BD then VS to prevent customer exposure to BA on connections over LHR.
It's not "odd" bagso, it's a reflection of reality. If the BA service was dropped tomorrow there's no way all of that capacity would suddenly be flying direct out of MAN, you'd leak to LBA of all places but more so to Virgin trains. Still glass half empty and all that jazz.....
Now genuine question, does anyone local have an informed view on why Emirates have leapt ahead leaving EY and QR behind at MAN? Is it really the A388 effect?