BA 476 then QR 3545 at Barcelona
London Heathrow → Barcelona → Santiago de Compostela
Timetable, Barcelona time
11:30BA 476 from London Heathrow at the gate
09:10QR 3545 to Santiago de Compostela leaves the gate
21 h 40 apart on the timetable, overnight
QR 3545 leaves 21 h 40 after BA 476 arrives on the timetable: more than half a day, so not a connection we count.