AA 5471 then DL 9960 at Atlanta
Washington National → Atlanta → New York LaGuardia
Timetable, Atlanta time
08:30AA 5471 from Washington National at the gate
06:00DL 9960 to New York LaGuardia leaves the gate
21 h 30 apart on the timetable, overnight
DL 9960 leaves 21 h 30 after AA 5471 arrives on the timetable: more than half a day, so not a connection we count.