AC 4121 then UA 1808 at San Francisco
Ontario → San Francisco → Newark
Timetable, San Francisco time
17:50AC 4121 from Ontario at the gatealso UA 5483
14:00UA 1808 to Newark leaves the gate
20 h 10 apart on the timetable, overnight
UA 1808 leaves 20 h 10 after AC 4121 arrives on the timetable: more than half a day, so not a connection we count.