GQ 311 then A3 366 at Athens
Samos → Athens → Santorini
Timetable, Athens time
15:40GQ 311 from Samos at the gate
13:30A3 366 to Santorini leaves the gate
21 h 50 apart on the timetable, overnight
A3 366 leaves 21 h 50 after GQ 311 arrives on the timetable: more than half a day, so not a connection we count.