QR 3507 then BA 495 at Barcelona
Alicante → Barcelona → London Heathrow
Timetable, Barcelona time
21:00QR 3507 from Alicante at the gate
20:50BA 495 to London Heathrow leaves the gatealso IB 3821, AA 6817, CX 7171, VY 9614
23 h 50 apart on the timetable, overnight
BA 495 leaves 23 h 50 after QR 3507 arrives on the timetable: more than half a day, so not a connection we count.