AA 4639 then B6 477 at JFK
Boston → New York → Jacksonville
Timetable, New York time
07:30AA 4639 from Boston at the gate
06:55B6 477 to Jacksonville leaves the gate
23 h 25 apart on the timetable, overnight
B6 477 leaves 23 h 25 after AA 4639 arrives on the timetable: more than half a day, so not a connection we count.