AA 5510 then DL 520 at Atlanta
Washington National → Atlanta → New York LaGuardia
Timetable, Atlanta time
23:23AA 5510 from Washington National at the gate
21:30DL 520 to New York LaGuardia leaves the gate
22 h 07 apart on the timetable, overnight
DL 520 leaves 22 h 07 after AA 5510 arrives on the timetable: more than half a day, so not a connection we count.