FR 1987 then FR 1976 at Dublin
Nantes → Dublin → Riga
Timetable, Dublin time
16:55FR 1987 from Nantes at the gate
09:45FR 1976 to Riga leaves the gate
16 h 50 apart on the timetable, overnight
FR 1976 leaves 16 h 50 after FR 1987 arrives on the timetable: more than half a day, so not a connection we count.