Flight Sydney Airport departs from Sydney Sydney Airport at 09:20 and arrives at Shenzhen Shenzhen Bao'an International Airport at 15:35.
The flighttime is about 9h 15m. The distance travelled ("as the bird flies"): 5617 Km. So the average speed is roughly 607 Km.
There is an 3 hour time difference between Sydney and Shenzhen