Flight Changi Airport departs from Singapore Changi Airport at 00:45 and arrives at Sydney Sydney Airport at 10:25.
The flighttime is about 7h 40m. The distance travelled ("as the bird flies"): 5577 Km. So the average speed is roughly 727 Km.
There is an 2 hour time difference between Singapore and Sydney
The best day to arrive at Singapore is Tuesday and it would be best to avoid Saturday, as prices are on average 118.46% higher than on Tuesday. (Average prices, based on 397214 datapoints.)
We have a lot more statistics for flights SQ 231 and between Singapore and Sydney.