FR 5150 then FR 340 at Dublin
Glasgow → Dublin → London Luton
Timetable, Dublin time
23:40FR 5150 from Glasgow at the gate
20:55FR 340 to London Luton leaves the gate
21 h 15 apart on the timetable, overnight
FR 340 leaves 21 h 15 after FR 5150 arrives on the timetable: more than half a day, so not a connection we count.