BA 478 then QR 3503 at Barcelona
London Heathrow → Barcelona → Santander
Timetable, Barcelona time
12:40BA 478 from London Heathrow at the gate
11:20QR 3503 to Santander leaves the gate
22 h 40 apart on the timetable, overnight
QR 3503 leaves 22 h 40 after BA 478 arrives on the timetable: more than half a day, so not a connection we count.