Pandalet
I suggest you search for the thread "CHC roster" which will answer alot of your questions.
Most Aberdeen based pilots live in or near Aberdeen so at the end of the day they go home. The companies provides no accommodation at Aberdeen and you work a normal roster with the usual FTL limits, i.e. a minimum of 12hrs off between day shifts.
There are few contracts that offer 15 days on 13 off and as one of those is about to finish there are experienced pilots looking for any spare places on other contracts so I would think that there will be very few vacancies in the future.
HF