Flight Brisbane Airport departs from Brisbane Brisbane Airport at 07:05 and arrives at Sydney Sydney Airport at 09:40.
The flighttime is about 2h 35m. The distance travelled ("as the bird flies"): 680 Km. So the average speed is roughly 263 Km.
The best day to arrive at Brisbane is Tuesday and it would be best to avoid Wednesday, as prices are on average 98.56% higher than on Tuesday. (Average prices, based on 5413571 datapoints.)
We have a lot more statistics for flights SQ 6691 and between Brisbane and Sydney.