DL 1091 then UA 8121 at San Francisco
Salt Lake City → San Francisco → Los Angeles
Timetable, San Francisco time
23:59DL 1091 from Salt Lake City at the gatealso VS 4542
23:12UA 8121 to Los Angeles leaves the gate
23 h 13 apart on the timetable, overnight
UA 8121 leaves 23 h 13 after DL 1091 arrives on the timetable: more than half a day, so not a connection we count.