Originally Posted by nene

That's a big NO at Delta. A reserve cannot just "pick up" open time on their days off.

but

A reserve may put in for a green slip (premium trip that would pay 2x pay for line holder or straight time above guarantee plus future days off for reserves.)

If a reserve gets the GS, they get the hours above guarantee, and the next days off (of scheduled on call days) of equal number of the trip. If they have no on call days left in the month, you get PayBack days, PB, which are very useful for dropping future trips, future on call days, or even extra vacation (a subject worthy of an small pamphlet) on how to use effectively.