FR 21 then BA 837 at Dublin
Newcastle → Dublin → London Heathrow
Timetable, Dublin time
23:55FR 21 from Newcastle at the gate
19:25BA 837 to London Heathrow leaves the gate
19 h 30 apart on the timetable, overnight
BA 837 leaves 19 h 30 after FR 21 arrives on the timetable: more than half a day, so not a connection we count.