The effective range of the aircraft depends on the amount of fuel loaded, vs the total mass of the aircraft. For this flight the mass of freight (human bodies plus baggage) was limited. A very large amount of fuel was loaded, comprising a larger proportion of the take off weight.
I read that all the passengers were accommodated in business class, which is at the front of the aircraft. So I wondered if their baggage was loaded to the rear of the cargo hold, to keep the center of gravity in the optimum location. The high fuel load would affect CofG as well.
Having an optimum CofG would presumably make the aircraft more efficient, by requiring less trim elevator input, so maybe there was some juggling of mass distribution as well.