UA 1246 then AA 2559 at Charlotte
Denver → Charlotte → Detroit
Timetable, Charlotte time
21:29UA 1246 from Denver at the gate
20:51AA 2559 to Detroit leaves the gate
23 h 22 apart on the timetable, overnight
AA 2559 leaves 23 h 22 after UA 1246 arrives on the timetable: more than half a day, so not a connection we count.