Flight Brisbane Airport departs from Brisbane Brisbane Airport at 16:15 and arrives at Melbourne Melbourne Airport at 18:40.
The flighttime is about 2h 25m. The distance travelled ("as the bird flies"): 1343 Km. So the average speed is roughly 556 Km.
The best day to arrive at Brisbane is Tuesday and it would be best to avoid Wednesday, as prices are on average 92.52% higher than on Tuesday. (Average prices, based on 1169879 datapoints.)
We have a lot more statistics for flights QF 631 and between Brisbane and Melbourne.