AA 5253 then UA 3917 at Houston
Washington National → Houston → Austin
Timetable, Houston time
10:05AA 5253 from Washington National at the gate
07:30UA 3917 to Austin leaves the gate
21 h 25 apart on the timetable, overnight
UA 3917 leaves 21 h 25 after AA 5253 arrives on the timetable: more than half a day, so not a connection we count.