A new manager comes in, wants to make a name for himself, clamps down on overtime, interferes with established ways of ensuring coverage, and guess what happens?
Yup. Not enough control staff to run the subsurface and Piccadilly lines last night. No problems for our intrepid new guvnor: the control room equipment can run itself! No, it can't. Still no problem: the staff can work through their meal reliefs. Er, no they can't.
Result: job up wall.