JU 8510 then UA 552 at San Francisco
New York JFK → San Francisco → Ontario
Timetable, San Francisco time
23:54JU 8510 from New York JFK at the gate
21:20UA 552 to Ontario leaves the gatealso CM 1456
21 h 26 apart on the timetable, overnight
UA 552 leaves 21 h 26 after JU 8510 arrives on the timetable: more than half a day, so not a connection we count.