UA 3913 then UA 410 at Houston
Denver → Houston → Miami
Timetable, Houston time
21:22UA 3913 from Denver at the gate
12:15UA 410 to Miami leaves the gate
14 h 53 apart on the timetable, overnight
UA 410 leaves 14 h 53 after UA 3913 arrives on the timetable: more than half a day, so not a connection we count.