OS 403 then QR 4704 at Barcelona
Vienna → Barcelona → Porto
Timetable, Barcelona time
17:20OS 403 from Vienna at the gate
08:35QR 4704 to Porto leaves the gate
15 h 15 apart on the timetable, overnight
QR 4704 leaves 15 h 15 after OS 403 arrives on the timetable: more than half a day, so not a connection we count.