Yes I see, but what about this? And I quote...
3.1. The following restrictions are inviolable with regard to the scheduling of Flight
Crew for this plan:
3.1.1 Prior to undertaking a ULR flight, all crew members shall be acclimatized. All crew members scheduled to operate a ULR flight sector with a published Flight Time of 16 hours or more shall be
assigned a ULR Standby on the day before the flight.
The last time I looked IAH is more than 2 hours time zone difference from DXB.
7