The SRC&C (that's some kind of safety check) for the new timetable identified that it would need seven new drivers. Management have brought in the timetable, but not the new drivers.
The result? Drivers are being refused short-notice requests for leave, and as on the other two lines, and constantly running past their knock-off time.
It seems to Tubeworker that if drivers on three lines are suffering the same problem, then a united fight by all three should bring the company to its senses.