F9 3206 then UA 3917 at Houston
Denver → Houston → Austin
Timetable, Houston time
09:52F9 3206 from Denver at the gate
07:30UA 3917 to Austin leaves the gate
21 h 38 apart on the timetable, overnight
UA 3917 leaves 21 h 38 after F9 3206 arrives on the timetable: more than half a day, so not a connection we count.