IB 5455 then UX 3644 at Barcelona
Paris Charles de Gaulle → Barcelona → Belgrade
Timetable, Barcelona time
23:35IB 5455 from Paris Charles de Gaulle at the gate
20:35UX 3644 to Belgrade leaves the gate
21 h apart on the timetable, overnight
UX 3644 leaves 21 h after IB 5455 arrives on the timetable: more than half a day, so not a connection we count.