FR 557 then BA 839 at Dublin
Manchester → Dublin → London Heathrow
Timetable, Dublin time
07:55FR 557 from Manchester at the gate
20:35BA 839 to London Heathrow leaves the gate
12 h 40 apart on the timetable
BA 839 leaves 12 h 40 after FR 557 arrives on the timetable: more than half a day, so not a connection we count.