FR 331 then FR 5172 at Dublin
London Luton → Dublin → Bristol
Timetable, Dublin time
17:15FR 331 from London Luton at the gate
11:25FR 5172 to Bristol leaves the gate
18 h 10 apart on the timetable, overnight
FR 5172 leaves 18 h 10 after FR 331 arrives on the timetable: more than half a day, so not a connection we count.