FR 6913 then OS 779 at Vienna
Milan → Vienna → Sofia
Timetable, Vienna time
08:00FR 6913 from Milan at the gate
21:25OS 779 to Sofia leaves the gate
13 h 25 apart on the timetable
OS 779 leaves 13 h 25 after FR 6913 arrives on the timetable: more than half a day, so not a connection we count.