BA 708 then LX 1390 at Zurich
London Heathrow → Zurich → Sofia
Timetable, Zurich time
10:25BA 708 from London Heathrow at the gate
07:15LX 1390 to Sofia leaves the gate
20 h 50 apart on the timetable, overnight
LX 1390 leaves 20 h 50 after BA 708 arrives on the timetable: more than half a day, so not a connection we count.