Anyone with any inside information on why BA feels it necessary to cancel all their programme
I believe it's because BA has pretty much all it's eggs (as in aircraft) in the LHR basket. Major delays there disrupt the whole BA operation, but most especially shorthaul, and possibly for several days. It doesn't have such a drastic effect on the global operation of airlines not based at Heathrow.
I'm not saying I agree with the tactic, and hats off to VS and BD for having a go, but following the runway closures this PM it might have been a smart move for BA though not great for their customers.