TR 263 then BA 16 at Changi
Surabaya → Singapore → London Heathrow
Timetable, Singapore time
22:55TR 263 from Surabaya at the gate
23:05BA 16 to London Heathrow leaves the gate
10 min apart on the timetable
The last days
TR 263 and BA 16 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.