BA 349 then EW 9463 at Heathrow
Nice → London → Düsseldorf
Timetable, London time
21:05BA 349 from Nice at the gate
12:15EW 9463 to Düsseldorf leaves the gate
15 h 10 apart on the timetable, overnight
EW 9463 leaves 15 h 10 after BA 349 arrives on the timetable: more than half a day, so not a connection we count.