I've just been through the cadet process. I got the base I asked for, but I visited the people that organise bases in person and maybe got lucky with my timing.
No two people's experiences seem the same, I know plenty of people that got the base they wanted straight from line training, some others didn't and got offered Dublin, Shannon, Prestwick or Bergamo.
All the guys I trained with (except one) are on a Brookfield contract as far as I know.
Expect 2-3 month in CAE/SAS on the TR, a week to a month at home waiting for your base check, then about 6 to 10 weeks line training, almost certainly away from home. Again, some guys got moved all over during this, I got the same base every week except one.
Only after line training (at least as a cadet) can you expect to be allocated a base. Why they put down your choices during your interview is a total mystery.
Expect to hang around on your training contract anything from a few days to a month following your line check until starting on a FR/Brookfield contract at your assigned base. You are still expected to fly at this point but only get paid the training contract rate (i.e. nowhere near enough to live off).
It took me about 7 months from starting training to my first real pay cheque (I'm ignoring the training pay I got during line-training which didn't even cover my accomodation/travel).
Good luck
