AA 5510 then DL 3121 at Atlanta
Washington National → Atlanta → Nashville
Timetable, Atlanta time
23:23AA 5510 from Washington National at the gate
23:00DL 3121 to Nashville leaves the gate
23 h 37 apart on the timetable, overnight
DL 3121 leaves 23 h 37 after AA 5510 arrives on the timetable: more than half a day, so not a connection we count.