Flight Gimhae International Airport departs from Busan Gimhae International Airport at 21:35 and arrives at Cebu Mactan-Cebu International Airport at 01:00.
The flighttime is about 4h 25m. The distance travelled ("as the bird flies"): 1722 Km. So the average speed is roughly 390 Km.
There is an 1 hour time difference between Busan and Cebu