Flight Changi Airport departs from Singapore Changi Airport at 08:25 and arrives at Osaka Kansai International Airport at 15:30.
The flighttime is about 6h 05m. The distance travelled ("as the bird flies"): 3803 Km. So the average speed is roughly 625 Km.
There is an 1 hour time difference between Singapore and Osaka
The best day to arrive at Singapore is Tuesday and it would be best to avoid Friday, as prices are on average 78.7% higher than on Tuesday. (Average prices, based on 159947 datapoints.)
We have a lot more statistics for flights SQ 620 and between Singapore and Osaka.