Flight Mactan-Cebu International Airport departs from Cebu Mactan-Cebu International Airport at 01:00 and arrives at Seoul Incheon International Airport at 06:30.
The flighttime is about 4h 30m. The distance travelled ("as the bird flies"): 1750 Km. So the average speed is roughly 389 Km.
There is an 1 hour time difference between Cebu and Seoul