BA 349 then AA 141 at Heathrow
Nice → London → New York JFK
Timetable, London time
21:05BA 349 from Nice at the gate
17:00AA 141 to New York JFK leaves the gate
19 h 55 apart on the timetable, overnight
AA 141 leaves 19 h 55 after BA 349 arrives on the timetable: more than half a day, so not a connection we count.