The stand planning unit also has to work to the airlines schedules as they have to have some sort of gameplan to work from.
If a flight is scheduled to land at 1100, but arrives at 1010 then they are off schedule so might have to wait. The time of day that the VS10/20/08 arrives is also one of the busiest times of day in T3. If it's outside the busy periods then obviously they will get a stand straight away.
At that time all stands will be occupied and you basically have to wait for another airline (or another company a/c) to depart or tow their a/c off before a stand will become clear.
Also as Silly Walks said, even if a stand is vacant - departing a/c that are towing back from a remote stand take priority.
We will also hold an a/c if it is on an immediate departure, i.e departing within 3-4 hours of arrival, otherwise we would coach the inbound if it was going to be a significant wait.
Things are going to get alot worse over the Summer in T3 as more of the stands get closed for building work, so there will be more holding and more coaching - GR8 !!!
