you dont get payed for A days but you do for res!
They roster more A days it seems because that gives them more flexibility.
The res periods only seem to be for 3 to 4 hrs in duration so you arnt usually covering all the days flights.
A days are only good for people who are out of town so that they dont have to come into within 2 hrs of the airport if they were on res , that is the only positive side to it basically. So if that is you then choose them if it aint then dont. You can tell they would prefer to keep you on A days when they kick up a fuss when you ask to be swapped back to res!
enough said!