DL 2398 then B6 411 at JFK
Atlanta → New York → Las Vegas
Timetable, New York time
17:36DL 2398 from Atlanta at the gate
06:30B6 411 to Las Vegas leaves the gate
12 h 54 apart on the timetable, overnight
B6 411 leaves 12 h 54 after DL 2398 arrives on the timetable: more than half a day, so not a connection we count.