Disagree. Overstaffing is endemic at BA. As a business they are fat and they know it. they have been shedding for years and are still lethargic.
I don't beleive that there is not a single available gate in the whole of BA at Heathrow that they could operated one 747-400 to Miami from, either from Terminal 1 or Terminal 4.
Perhaps they are missing the old BOAC days at Terminal 3.
It's mess. Roll on T5