Back in 1998, Mrs. Emw9000 and I had the pleasure of using the stairway at the old Kai-Tak airport in HKG. We were on an NW 747-400 and they used 2 staircases, one at the front of the aircraft and one at the rear. I agree with a previous post that it is probably airport dependent. Back in those days gates were at a premium in HKG.