QR 3692 then BA 479 at Barcelona
Rome → Barcelona → London Heathrow
Timetable, Barcelona time
17:05QR 3692 from Rome at the gate
13:35BA 479 to London Heathrow leaves the gate
20 h 30 apart on the timetable, overnight
BA 479 leaves 20 h 30 after QR 3692 arrives on the timetable: more than half a day, so not a connection we count.