Only about 3 or 4 were from London. About 20 crew have been based in Sydney from London over the last few weeks to complete training and fly on the aircraft. Most have returned home already and the remainder on January 5th.
Of course when the aircraft commences services between SYD and LHR the SIN-LHR-SIN sectors will be crewed by the London base. Australian crew will now operate on the QF9 and QF10 as Australian crew are entitled to one flight to London everyday.
When the crew return to London they will train the rest of the base in time for the January 16th.