UA 3236 then UA 1971 at Houston
Midland → Houston → Las Vegas
Timetable, Houston time
18:30UA 3236 from Midland at the gate
14:30UA 1971 to Las Vegas leaves the gate
20 h apart on the timetable, overnight
UA 1971 leaves 20 h after UA 3236 arrives on the timetable: more than half a day, so not a connection we count.