UA 3901 then AS 3210 at San Francisco
Hong Kong → San Francisco → Santa Ana
Timetable, San Francisco time
16:34UA 3901 from Hong Kong at the gate
11:26AS 3210 to Santa Ana leaves the gate
18 h 52 apart on the timetable, overnight
AS 3210 leaves 18 h 52 after UA 3901 arrives on the timetable: more than half a day, so not a connection we count.