UA 3902 then DL 1216 at Houston
Toronto → Houston → Los Angeles
Timetable, Houston time
08:27UA 3902 from Toronto at the gate
07:00DL 1216 to Los Angeles leaves the gate
22 h 33 apart on the timetable, overnight
DL 1216 leaves 22 h 33 after UA 3902 arrives on the timetable: more than half a day, so not a connection we count.