DL 4959 then B6 215 at JFK
Jacksonville → New York → San Francisco
Timetable, New York time
10:09DL 4959 from Jacksonville at the gate
10:00B6 215 to San Francisco leaves the gate
23 h 51 apart on the timetable, overnight
B6 215 leaves 23 h 51 after DL 4959 arrives on the timetable: more than half a day, so not a connection we count.