The market for LCY-JER today is the same market today as it was five years ago, ten years ago and twenty years ago. It is predominantly business based and will be the same ten years from now (depending on Brexit effect on the City of London). It has never been made a success by any operator and BA get far more mileage out of their Gatwick route than they ever would out of City. I'll say it again, if BA were interested in it, it would have been tried already.