BA 339 then AA 79 at Heathrow
Nice → London → Dallas-Fort Worth
Timetable, London time
12:15BA 339 from Nice at the gate
11:50AA 79 to Dallas-Fort Worth leaves the gate
23 h 35 apart on the timetable, overnight
AA 79 leaves 23 h 35 after BA 339 arrives on the timetable: more than half a day, so not a connection we count.