Monday 6 December 2021's QF2, the 0950 hours LHR - DRW - SYD pushed back at about 0953 in London but from the limited amount of what one can see on FR24, it looks as if B789 VH-ZNG is either returning to the terminal or joining the back of the queue again. Further information would be welcome.
It could be a problem with the aircraft, or a passenger, or something more benign.
UPDATE: By 2130 AEDT (1030 UK time), the aircraft had disappeared from the FR24 site. From past AFF discussion, sometimes this is due to interference from a building.
FURTHER UPDATE: By 2132 (1032), the FR24 site was claiming 'delayed 2006 (hours' that may refer to a new delayed landing time in DRW on Tuesday 7, which if so would be 501 minutes later than the schedule4d at gate time of 1145. (By 2144 AEDT, FR24 had updated it to '2015 hours'.
The QF website 'flight status' however is far more optimistic, suggesting that QF2 will depart LHR at 1045 - in seven minutes - so it may just be a passenger became sick and has had to alight back in the terminal. QF claims DRW at gate arrival time of 1220, only 35 down.
By 2150 AEDT (1050 UK time), the Heathrow Airport site was showing a suggested departure at 1130, 100 minutes late.
But at 2151 AEDT, the QF website suggested '1145' as the time the plane would push back. with DRW Tuesday arrival to become 1325, 100 late.