Some simple maths:
Total fuel 9360kg
Minus fixed reserve of 900kg gives
8460kg
Taxi/takeoff/climb first hour 3000kg gives
5460kg
5460kg/2200 per hour burn gives 2.48 hours.
1+2.48 = 3.48 hrs @ 380ktas equals
1322nm range nil wind with no variable reserve.
This is somewhat less than the reported 1600nm sector.
I rest my case.