There are too much elements that I don't know to help you out...
eg airline, ETD, ETA etc...
The best advice that I can give to you, as you work on the airport, is have a quick look in the cabin when the aircraft is on the ground @ BRU
time @ the airport the day you leave, is a must to get (maybe) the seat that you want!!!(-> earlier then the requested 2 hrs!)
Drop me an e-mail and we sort things out.
There is more in life then Airliners.net... Belgae Gallorum Fortissimi