Perhaps then they take into consideration your requests where possible dependant on operational requirements. I know for a fact that my friend got asked which he wanted to do, and he asked Fastjet, after 1FTS, he went Valley, was creamed to stay at Valley, then after a tour there went onto his OCU. He's now a GR4 Jocky.
Eitherway, you'd be lucky to get into the RAF these days as any pilot.
The current intake at FTS Linton consists of 3 students. Thats 3 new pilots for the entire 2006 intake.