AA 5510 then DL 2398 at Atlanta
Washington National → Atlanta → New York JFK
Timetable, Atlanta time
23:23AA 5510 from Washington National at the gate
15:16DL 2398 to New York JFK leaves the gate
15 h 53 apart on the timetable, overnight
DL 2398 leaves 15 h 53 after AA 5510 arrives on the timetable: more than half a day, so not a connection we count.