KL 515 then KL 1007 at Schiphol
Dar es Salaam → Amsterdam → London Heathrow
Timetable, Amsterdam time
07:45KL 515 from Dar es Salaam at the gate
11:45KL 1007 to London Heathrow leaves the gate
4 h apart on the timetable
The last days
KL 515 and KL 1007 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.