UA 3902 then UA 2600 at Houston
Toronto → Houston → Los Angeles
Timetable, Houston time
08:27UA 3902 from Toronto at the gate
07:15UA 2600 to Los Angeles leaves the gate
22 h 48 apart on the timetable, overnight
UA 2600 leaves 22 h 48 after UA 3902 arrives on the timetable: more than half a day, so not a connection we count.