B6 616 then DL 1428 at JFK
San Francisco → New York → Miami
Timetable, New York time
07:24B6 616 from San Francisco at the gate
19:40DL 1428 to Miami leaves the gate
12 h 16 apart on the timetable
DL 1428 leaves 12 h 16 after B6 616 arrives on the timetable: more than half a day, so not a connection we count.