Flight Changi Airport departs from Singapore Changi Airport at 16:05 and arrives at Jeddah King Abdulaziz International Airport at 20:50.
The flighttime is about 9h 45m. The distance travelled ("as the bird flies"): 7126 Km. So the average speed is roughly 731 Km.
There is an 5 hour time difference between Singapore and Jeddah