F9 3059 then DL 30 at Atlanta
Miami → Atlanta → New York JFK
Timetable, Atlanta time
13:56F9 3059 from Miami at the gate
18:40DL 30 to New York JFK leaves the gate
4 h 44 apart on the timetable
The last days
F9 3059 and DL 30 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.