A3 981 then GQ 430 at Athens
Sofia → Athens → Skiathos
Timetable, Athens time
12:30A3 981 from Sofia at the gate
12:20GQ 430 to Skiathos leaves the gate
23 h 50 apart on the timetable, overnight
GQ 430 leaves 23 h 50 after A3 981 arrives on the timetable: more than half a day, so not a connection we count.