On 27 July 2019, a fuel configuration advisory was annunciated on a Boeing 767-300 about to depart Auckland as a result of wing tank imbalance. Having established there was no evidence of a fuel leak, they planned to correct the imbalance in flight but then delayed this until it had exceeded the permitted limits. The fault was only verbally reported after flight and the aircraft continued to operate without centre tank use with maintenance remaining unaware of the fault for several days. The cause of imbalance was a fuel system fault subject to a crew response which was not followed.