"Back in the day..." everything revolved around 75 hours per month, for pay. You didn't get paid more, if you flew more, you got a bow wave.

The bid sheet lines were built 68 to 75hrs. and reserve was only 70. If, due to re-routes, over-fly, holding, what ever, you ended up flying say, 80 hours in a month, the "extra" 5 hours was called your "Bow Wave" and pushed into the next month...or you could put the 5 hours into your Bank, to be withdrawn in a "short" month, to bring you up to 75.

Say next month your line was only 71 hours, well, if you had 4 hours of bow wave, you would get your 75 hours pay. But if you got a 75 hour line and over-flew it to say, 85, well, now your bow wave into the next month would be the 5 from last month, plus the extra 10 in this month, for a 15 hour bow wave going into the 3rd month.

In no case would you be paid 85 hours, (like today) anything on top of 75 was either going into your bank or into your bow wave. If over a few months, you accumulated say, 20 hours in your BW, you could drop a 20 hour trip and use your bow wave to cover it, to get paid 75. If you were constantly getting called out (inverse assignements) to fly over 75 hours, you didn't get paid extra, you got a bigger bow wave.

When I was hired in Sept. of 1985, the company was so short of pilots, there were many 727 Engineers with 200+ hour bow waves, because the company "froze" their bow waves, ie. would not let them drop a whole month (or even one trip) to use up their bow waves.

After a 4 day trip, guys were getting re-routes in the jetway as they tried to go home, from the gate agents (no cell phones back then), so to keep that from happening, a lot of Engineers would run off the plane via the aft airstairs, across the ramp, to the parking lot.

Finally, DALPA said, "Enough, you MUST HIRE pilots!" and they did. My first 6 months, as one of the most junior engineers in MIA, I flew some of the best lines in the bid package, because they finally had to allow guys to use up their 200hr. bow waves. So guys were dropping their entire 75 hour lines, and I, being the junior guy, got assigned these lines!