A3 504 then UX 1684 at Istanbul
Thessaloniki → Istanbul → Madrid
Timetable, Istanbul time
16:55A3 504 from Thessaloniki at the gate
16:45UX 1684 to Madrid leaves the gate
23 h 50 apart on the timetable, overnight
UX 1684 leaves 23 h 50 after A3 504 arrives on the timetable: more than half a day, so not a connection we count.