On Tuesday 3 January, QF12 (B744) departed JFK at 2145, 225 minutes behind schedule, arriving LAX at 0057 hours on Wednesday 4, 242 late.
A388 VH-OQB on the continuation of QF12 from LAX to SYD has a timetabled departure of 2230 hours (Tuesday 3.) This became 0130 hours on Wednesday 4 to connect from JFK, but at 2140 AEDT was altered to become 0300, meaning that even if the flight picks up half an hour it will still be four hours late into SYD - QF is predicting a 1245 hours early afternoon arrival, 255 minutes late.
The more critical cog in the wheel as regards punctuality (because QF12 can have a reasonable layover in SYD even if a few hours late in arriving, and form QF1 at 1645 hours to DXB and LHR, but normally QF16 after arriving in BNE has to go back to LAX), QF16, is still publicly displaying as an 0230 hours LAX departure on Wednesday 4 for BNE but has yet to do so as at 0244 hours LAX time.
It is looking like QF15 on Wednesday 4 will be more delayed than the 65 minutes late (1215 hours) QF is predicting ex BNE.
UPDATE: QF16 (B744 VH-OEH) commenced its pushback in LAX at 0306, 226 minutes tardy. As is often the case, QF may revise its arrival time in BNE once it has taken off.
As at 0314 LAX time (2214 AEDT), QF12 appears not to have yet moved away from its terminal gate. I do not know what time the flight crew signed on but hopefully they are still well within their duty hours limitations - (18 hours if I recall with a possible extension by agreement to 20?)