DL 1223 then AA 4576 at Atlanta
Cincinnati Northern Kentucky → Atlanta → Washington National
Timetable, Atlanta time
16:33DL 1223 from Cincinnati Northern Kentucky at the gate
13:39AA 4576 to Washington National leaves the gate
21 h 06 apart on the timetable, overnight
AA 4576 leaves 21 h 06 after DL 1223 arrives on the timetable: more than half a day, so not a connection we count.