It's monthly average Line value (ALV) that ranges from 72-82.

To get a line you have to bid within the line construction window (LCW) that is 7.5 hours above or below ALV.

Once schedules are released you can white slip (straight time) up to ALV +15.

You can go over ALV +15 by picking up Pilot to Pilot swap board trips IF they don't violate any FAR limits in regards to hours.

Green slip is doubletime but does not count as credit time so it doesn't affect pick up limits.