B6 478 then B6 615 at JFK
Jacksonville → New York → San Francisco
Timetable, New York time
18:00B6 478 from Jacksonville at the gate
17:55B6 615 to San Francisco leaves the gate
23 h 55 apart on the timetable, overnight
B6 615 leaves 23 h 55 after B6 478 arrives on the timetable: more than half a day, so not a connection we count.