Flight Taoyuan International Airport departs from Taipei Taoyuan International Airport at 21:10 and arrives at Hong Kong Hong Kong International Airport at 23:00.
The flighttime is about 1h 50m. The distance travelled ("as the bird flies"): 826 Km. So the average speed is roughly 451 Km.
The best day to arrive at Taipei is Thursday and it would be best to avoid Monday, as prices are on average 140.59% higher than on Thursday. (Average prices, based on 4166348 datapoints.)
We have a lot more statistics for flights CI 921 and between Taipei and Hong Kong.