AA 1610 then UA 616 at Denver
Charlotte → Denver → San Francisco
Timetable, Denver time
10:06AA 1610 from Charlotte at the gate
09:50UA 616 to San Francisco leaves the gate
23 h 44 apart on the timetable, overnight
UA 616 leaves 23 h 44 after AA 1610 arrives on the timetable: more than half a day, so not a connection we count.