on the half hour

[jasonlulu_2000]

---Do you think we've missed the bus?
--Don't worry. It never exactly comes on the half hour like it should.

Should I replace "on" with "at" since we often say "at 8:30"?

Plus, if a bus comes on the half hour, does it mean it often arrives at 7:30, 8:30, 9:30...?

Thanks!

Jason

[Rover_KE]

---Do you think we've missed the bus?
--Don't worry. It never comes exactly on the half hour like it should.

Should I replace "on" with "at" since we often say "at 8:30"? No.

Plus, if a bus comes on the half hour, does it mean it often arrives at 7:30, 8:30, 9:30...? Yes.

Rover

[emsr2d2]

There are two standard time phrases like this - "on the hour" and "on the half hour". If a bus service is scheduled to stop somewhere twice each hour, on the hour and on the half hour, then it should come at exactly 8.00, 8.30, 9.00, 9.30 etc.