DL 4995 then B6 1523 at JFK
Nashville → New York → Los Angeles
Timetable, New York time
13:48DL 4995 from Nashville at the gate
17:59B6 1523 to Los Angeles leaves the gate
4 h 11 apart on the timetable
The last days
DL 4995 and B6 1523 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.