FR 339 then FR 457 at Dublin
London Luton → Dublin → Leeds
Timetable, Dublin time
14:30FR 339 from London Luton at the gate
05:55FR 457 to Leeds leaves the gate
15 h 25 apart on the timetable, overnight
FR 457 leaves 15 h 25 after FR 339 arrives on the timetable: more than half a day, so not a connection we count.