DL 512 then DL 2398 at Atlanta
Dallas → Atlanta → New York JFK
Timetable, Atlanta time
18:59DL 512 from Dallas at the gate
15:16DL 2398 to New York JFK leaves the gate
20 h 17 apart on the timetable, overnight
DL 2398 leaves 20 h 17 after DL 512 arrives on the timetable: more than half a day, so not a connection we count.