AA 4343 then B6 955 at JFK
Nashville → New York → Washington National
Timetable, New York time
21:00AA 4343 from Nashville at the gate
20:55B6 955 to Washington National leaves the gate
23 h 55 apart on the timetable, overnight
B6 955 leaves 23 h 55 after AA 4343 arrives on the timetable: more than half a day, so not a connection we count.