FR 3976 then BA 825 at Dublin
Barcelona → Dublin → London Heathrow
Timetable, Dublin time
14:40FR 3976 from Barcelona at the gate
08:50BA 825 to London Heathrow leaves the gate
18 h 10 apart on the timetable, overnight
BA 825 leaves 18 h 10 after FR 3976 arrives on the timetable: more than half a day, so not a connection we count.