Flight Hong Kong International Airport departs from Hong Kong Hong Kong International Airport at 20:55 and arrives at Beijing Beijing Capital International Airport at 00:30.
The flighttime is about 3h 35m. The distance travelled ("as the bird flies"): 890 Km. So the average speed is roughly 248 Km.
The best day to arrive at Hong Kong is Saturday and it would be best to avoid Wednesday, as prices are on average 602.4% higher than on Saturday. (Average prices, based on 204149 datapoints.)
We have a lot more statistics for flights HX 304 and between Hong Kong and Beijing.