I'm sure if was the case that 3 planes needed to land and have limited fuel supplies then obviously they will make provisions to get the planes on the ground.
Say all London airports were closed due to snow and MAN could accept 1, either the other two would have to go out into Europe or if MAN's 2nd runway was closed - maybe putting them there would work? I am sure that if they need to get on the ground, they will do somewhere! They can only stay in the air for a certain time!