Right to request 50% and 75% available, work either 2 or 1 fixed week off each month and you bid at stage 2. For the senior guys it's write your own roster effectively, for the more junior you get whats left over.
For what it's worth i'm full time in the bottom 20 of my fleet and I get a tripline every month, usually with a compete weekend off and a partial with 12-14 days off in total at home.