From the pilots end, ops will file a flight plan that will be something like EGBB HON MOSUN PERUP then enroute. The route is only open certain times of day and days of the week. We would call for clearance as usual. Ground/delivery will come back with something like "climb straight ahead 3 miles, left turn direct Mosun climb altitude 6000' " for runway 33, or for 15 "standard noise, right turn direct Mosun climb altitude 6000'. If memory serves 15 noise is runway heading to 1nm IBIR, right turn track 170 until 4 miles IBIR then we would hang a right towards mosun.