EI 3555 then FR 122 at Dublin
Edinburgh → Dublin → London Gatwick
Timetable, Dublin time
18:35EI 3555 from Edinburgh at the gate
15:55FR 122 to London Gatwick leaves the gate
21 h 20 apart on the timetable, overnight
FR 122 leaves 21 h 20 after EI 3555 arrives on the timetable: more than half a day, so not a connection we count.