1.67
Airbus certifies to European standards which don't require factoring for any in flight calculation, same as the FAA.
The aircraft is operated here under Australian rules which do require in flight factoring.
CASA is the Australian regulator, not Airbus.
Perhaps your airline has an exemption from 20.7.1b to follow the Airbus method in lieu of the regs? It would probably be a straight forward exemption to obtain based on the fact that everyone else in the world does it that way.