UA 1023 then DL 670 at San Francisco
Boston → San Francisco → New York JFK
Timetable, San Francisco time
10:59UA 1023 from Boston at the gatealso NH 7003, CA 7222
23:05DL 670 to New York JFK leaves the gatealso AM 4305, VS 4848, LA 6189, KQ 7055
12 h 06 apart on the timetable
DL 670 leaves 12 h 06 after UA 1023 arrives on the timetable: more than half a day, so not a connection we count.