How long was Dilys late?

M: Dilys, I told you to be here at 7:00 o’ clock, but it’s 8:30 now. Why were you late today?
W: I overslept and missed the bus.

M: I really must go now, Cathy. We’re going to take the children to see a film tonight.
W: Well, Jack. In that case, I won’t keep you.