BA 640 then GQ 670 at Athens
London Heathrow → Athens → Istanbul
Timetable, Athens time
01:30BA 640 from London Heathrow at the gate
19:15GQ 670 to Istanbul leaves the gate
17 h 45 apart on the timetable
GQ 670 leaves 17 h 45 after BA 640 arrives on the timetable: more than half a day, so not a connection we count.