JU 8510 then UA 8121 at San Francisco
New York JFK → San Francisco → Los Angeles
Timetable, San Francisco time
23:54JU 8510 from New York JFK at the gate
23:12UA 8121 to Los Angeles leaves the gate
23 h 18 apart on the timetable, overnight
UA 8121 leaves 23 h 18 after JU 8510 arrives on the timetable: more than half a day, so not a connection we count.