UA 3852 then AS 211 at San Francisco
Seoul → San Francisco → New York JFK
Timetable, San Francisco time
08:46UA 3852 from Seoul at the gate
07:00AS 211 to New York JFK leaves the gatealso QR 4271, LA 6303, LA 6323, LA 7146, LA 8951
22 h 14 apart on the timetable, overnight
AS 211 leaves 22 h 14 after UA 3852 arrives on the timetable: more than half a day, so not a connection we count.