DL 712 then DL 2398 at Atlanta
Washington National → Atlanta → New York JFK
Timetable, Atlanta time
21:38DL 712 from Washington National at the gate
15:16DL 2398 to New York JFK leaves the gate
17 h 38 apart on the timetable, overnight
DL 2398 leaves 17 h 38 after DL 712 arrives on the timetable: more than half a day, so not a connection we count.