Ah, the "You bid it, you fly it arguement". Not totally unreasonable . . there ARE some advantages . . . home everyday, get off in the AM and don't start again till the PM, so 3 days off is really more like 4 1/2 days off, only flying 50-60 hrs per bid. Excellent for commuting.
Yes they are published pairings.
Yes, reserve guys get called out to fly the worst,(because the lineholders call in sick or fatigued or trade them away . . see below)
Yes, there are shifts all over the clock. One CDO shift might start at 7pm and fly 4 legs til 10 am the next morning (2 legs after midnight w/ a 2.5 hr nap in there somewhere). Duty off, drive home, get 5 hrs of sleep
if you're lucky, (see below, under the "quote") Perfectly legal.
Or, the next day, you might start at 10pm then fly until noon the next day.
Or, the next day, you might have a single leg out to an outstation, and check into a hotel for 6 hours. Oh wait . . .
DON'T SLEEP, because you'll be f'd when you do the fly-all-night the next night. You're a "night guy" now, remember?
These shifts are all over the clock even for those who bid them. Whereas Mesa used to only put CDO's on dedicated CDO lines, they have recently begun the practice of puting a few CDO shifts in the middle of "normal" day flying lines. Again, perfectly legal.
And perfectly potty.
couple of questions...
Are those published pairings? Are those guys on reserve getting called out for this? Is it strictly the backside flying or are there more flights than the one back to the base in the morning?
I'm not aware of how those pairings are handled at the airline you're at, but where I'm at they are very senior.
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Sample CDO shift with 4 legs, 2 after midnight.
- 1900: duty on.
- Fly 4 legs. 2.5 hr nap in APU inop, stinky-lav CRJ w/ 2-3 strangers. Two will snore. 1 will fart. (that would be me)

- 1000 am: duty off
- 11 am: back from drive home (25 min to car lot, 35 min drive home)
- 1130 am: Sleep. Blessed sleep. For 5.5 hours.
- 1700: Get up. Quick 30 min exercise (have to conduct lives that don't contribute to fatigue, right?) 30 min shower, shave, press uniform, shine shoes.
- 1800: Drive back to the airport.
- 1900: repeat.
By day 3, you're dead. Absolutely bonkers. Anyone who DOSEN"T called fatigued on day 3 is a liar, and by day 4 is probably the walking dead.