FR 10 then BT 686 at Madrid
Dublin → Madrid → Riga
Timetable, Madrid time
20:00FR 10 from Dublin at the gate
17:15BT 686 to Riga leaves the gate
21 h 15 apart on the timetable, overnight
BT 686 leaves 21 h 15 after FR 10 arrives on the timetable: more than half a day, so not a connection we count.