lemurian:
- a T/O at 22:30 z
- a landing at 09:00 z
- The rest period of each pilot will be 10:30 - 1 = 9:30 : 3 = 3:10 hrs.
- They 'd then had crew changes at :
TOC + 3:10 = 23:00 z + 3:10 = 02:10 z : first crew change, and
02:10 z + 3:10 = 05:20 : second crew change.
Am not familiar with AF traditions, but:
Disadvantage of dividing in 3 stretches is that 2 pilots end up with a long "sit" (6' 20" min). So at my airline it is usually divided in 6 stretches, ie in your example first 3x 1hr and then 3x 2hr10min. Enough left for a descent nap and enough rotations to stay awake upfront!
Ergo, hard to make conclusions who were in the cockpit.