UAL the offender last month, flight delayed (SFO-HKG), a decision was made to load so much cargo that fuel to destination was not possible, flight was then rerouted through AKC (left about three hours late). About one hour out of Anchorage it was determined by ops that the crew wouldn't have the duty to continue to HKG (oops), the told crew was given instructions to divert to SFO.