Matt O'Sullivan of 'SMH' has written an excellent article "There's no one: pilot sickness, faults stretch Qantas" (also on 'The Age' and 'Cnaberra Times' websites re how QF27 was the subject of an urgent email from the Manager, Base Operations (strangely in MEL not SYD) when a FO could not at first be found. This flight on Sunday 3 departed SYD at 1318, 43 late, arriving SCL at 1152, 42 late. The returning QF28 departed SCL 26 late at 1356, arriving in SYD on Monday 4 June not long ago at 1834 hours, 34 late.
The article also discusses problems with the A333 fleet including the engine problem on Friday 1 June that forced A333 VH-QPI back to SYD on QF23, the 0950 hours SYD - BKKK that had departed about two hours late.
QF's claim that it has 'a level of redundancy' in case of problems is questionable.
I've suggested before that at least from observation, the A333 fleet is being worked too hard.
Good maintenance is important, but even if this is a 'given', there doesn't seem to be much ability from QF to, for instance, substitute an A332 for an A333 if the latter is suddenly available. It's complex and aircraft may be 'anywhere' and there's lots of other considerations such as crewing, the number of cycles each aircraft does, seating capacity varying, catering, maintenance schedules and probably a zillion other things, but to have six international flights delayed during the weekend when the weather was benign is unimpressive.
FR24 indicates that QPI remains grounded in SYD; as noted above, today QF117 SYD - HKG was cancelled.
Thursday to Monday inclusive tends to be the busiest days for QFi (a comment that could be made also about other airlines) so perhaps tomorrow will be less disrupted.