Flight Taoyuan International Airport departs from Taipei Taoyuan International Airport at 08:20 and arrives at Singapore Changi Airport at 13:05.
The flighttime is about 4h 45m. The distance travelled ("as the bird flies"): 2134 Km. So the average speed is roughly 449 Km.
The best day to arrive at Taipei is Thursday and it would be best to avoid Wednesday, as prices are on average 103.47% higher than on Thursday. (Average prices, based on 714086 datapoints.)
We have a lot more statistics for flights GA 9994 and between Taipei and Singapore.