AY 1252 then FI 343 at Helsinki
Budapest → Helsinki → Reykjavík
Timetable, Helsinki time
15:00AY 1252 from Budapest at the gate
14:00FI 343 to Reykjavík leaves the gate
23 h apart on the timetable, overnight
FI 343 leaves 23 h after AY 1252 arrives on the timetable: more than half a day, so not a connection we count.