UA 1246 then AA 1502 at Charlotte
Denver → Charlotte → Nashville
Timetable, Charlotte time
21:29UA 1246 from Denver at the gate
20:05AA 1502 to Nashville leaves the gate
22 h 36 apart on the timetable, overnight
AA 1502 leaves 22 h 36 after UA 1246 arrives on the timetable: more than half a day, so not a connection we count.