Flight Sydney Airport departs from Sydney Sydney Airport at 07:05 and arrives at Brisbane Brisbane Airport at 08:35.
The flighttime is about 1h 30m. The distance travelled ("as the bird flies"): 680 Km. So the average speed is roughly 453 Km.
The best day to arrive at Sydney is Friday and it would be best to avoid Saturday, as prices are on average 118.57% higher than on Friday. (Average prices, based on 2623612 datapoints.)
We have a lot more statistics for flights QF 504 and between Sydney and Brisbane.