UA 3909 then UA 2127 at San Francisco
Cancún → San Francisco → Los Angeles
Timetable, San Francisco time
15:10UA 3909 from Cancún at the gate
06:00UA 2127 to Los Angeles leaves the gatealso AV 2163, UA 3904, NZ 9260
14 h 50 apart on the timetable, overnight
UA 2127 leaves 14 h 50 after UA 3909 arrives on the timetable: more than half a day, so not a connection we count.