GQ 681 then A3 358 at Athens
Sofia → Athens → Santorini
Timetable, Athens time
21:55GQ 681 from Sofia at the gate
16:55A3 358 to Santorini leaves the gate
19 h apart on the timetable, overnight
A3 358 leaves 19 h after GQ 681 arrives on the timetable: more than half a day, so not a connection we count.