UA 1970 then AS 1831 at San Francisco
Cleveland → San Francisco → Los Angeles
Timetable, San Francisco time
21:45UA 1970 from Cleveland at the gatealso VA 8489, NZ 9046, OZ 9526
15:38AS 1831 to Los Angeles leaves the gatealso TN 2348, AY 2513, QR 3365, QR 8834
17 h 53 apart on the timetable, overnight
AS 1831 leaves 17 h 53 after UA 1970 arrives on the timetable: more than half a day, so not a connection we count.