GQ 681 then A3 712 at Athens
Sofia → Athens → Barcelona
Timetable, Athens time
21:55GQ 681 from Sofia at the gate
16:40A3 712 to Barcelona leaves the gate
18 h 45 apart on the timetable, overnight
A3 712 leaves 18 h 45 after GQ 681 arrives on the timetable: more than half a day, so not a connection we count.