FI 450 then BA 358 at Heathrow
Reykjavík → London → Lyon
Timetable, London time
10:50FI 450 from Reykjavík at the gate
10:15BA 358 to Lyon leaves the gate
23 h 25 apart on the timetable, overnight
BA 358 leaves 23 h 25 after FI 450 arrives on the timetable: more than half a day, so not a connection we count.