I'm flying there today!! On my BA flight we take off at 2200 today (thurs) and land 0605(local) Saturday morning, with about a 3 hr stop in Bangkok to refuel. On my ticket it reckons total time of 23hrs 50 mins. I think I'll be going through Oz immigration like a zombie!!
have a good time out there sddsdean. I also took this flight years ago to Brisbane though, also departed at 10pm and arrived 2 days later! By the end of your trip you will just stink of B.O. and be falling asleep on your way to the hotel but then you wont be able to get to sleep once you're there due to jetlag!