Something to keep in mind about relief lines. Scheduling doesn't know how many relief lines are going to have a month of flying trips in them until late in the month. Let's say there are 15 relief lines to bid in the initial bid. After they adjusts everyone's schedule for training/vacation/etc, they then build the relief lines. They may only build 6-7 lines. Then those people bid in a secondary bid for either those 6-7 lines or another 8 reserve lines (in this example) that scheduling built for the secondary bid. Those reserve lines have 14 days off instead of 12. So just because you can hold a relief line doesn't mean you won't be on reserve.