What time is train supposed to leave?

M: The train should have left at 10: 50. Why are we still waiting here?
W: I’m afraid the train is late again, darling! It’ s so boring. We have been waiting since 10: 10.
M: And we are not sure when it will leave, aren’ t we?
W: The broadcast says that it will leave at 12: 20.
M: Oh we have another half an hour to wait. How terrible!