UA 648 then DL 2112 at San Francisco
Newark → San Francisco → New York JFK
Timetable, San Francisco time
09:30UA 648 from Newark at the gatealso TP 8490, VA 8516, NZ 9121
21:35DL 2112 to New York JFK leaves the gatealso AM 4443, VS 4856, KQ 7007
12 h 05 apart on the timetable
DL 2112 leaves 12 h 05 after UA 648 arrives on the timetable: more than half a day, so not a connection we count.