Of interest.
Refuel two aircraft at the same time with the same fuel.
Action fuel/water drainage checks at 2/3 hours on one and do the other at 9/10 hours, results will tend to be different, more water will normally be recovered at the 9/10 hours checks.
After a long smooth cruise could guess results would be the same.
But now think the 777RR have new drills for crew to incease fuel flow to deal with the poss of water build up.