This happens from time to time and although abnormal, this is what crew who work for proper airline do when they find that they will not have enough fuel to complete the flight, with appropriate reserves. Modern day flight planning systems will normally allow an aircraft to depart with exactly the correct amount of fuel plus reserves. But in this part of the world (near the equator), the grid used by meteorologists is pretty coarse and the data very sparse which results in incorrect wind data being used for flight planning. What would really be worrying is if the crew found they were "behind" flight plan fuel overhead Adelaide but I'll stick my neck out and say they (and head office) knew they were "short" shortly after top of climb. Therefore, they re-planned in flight and went to Adelaide. Good guys!
Making a report to Australian Transport Bureau is hardly surprising, it could have been a safety issue and is probably a legal requirement. But any further action by them would be pointless as almost certainly Qantas will be keener to prevent a reoccurrence than they are. Unfortunately though, they'll probably be crawling over the crew, paperwork and anything else they can get their hands in attempt to justify their own existence.
And just to be a bit more controversial, here's little question: Do you think that long haul aircraft always depart with enough fuel to complete their flights?
PM
Answer: No and in fact the answer is "hardly ever." Most aviation authorities allow aircraft to depart with less than the "minimum" required amount of fuel. But when in flight, they then plan to use their contingency fuel, unburnt until that point, which allows then to effectively "divert" to their destination. Not surprisingly there are conditions attached to such operation and every now and again you are unable to land at your destination. Which is a pretty expensive exercise.