DE 1669 then 4Y 1408 at Frankfurt
Heraklion → Frankfurt am Main → Varna
Timetable, Frankfurt am Main time
17:50DE 1669 from Heraklion at the gate
14:404Y 1408 to Varna leaves the gate
20 h 50 apart on the timetable, overnight
4Y 1408 leaves 20 h 50 after DE 1669 arrives on the timetable: more than half a day, so not a connection we count.