AA 1225 then AA 4721 at Boston
Miami (MIA) → Boston → New York JFK
Timetable, Boston time
12:44AA 1225 from Miami (MIA) at the gate
17:28AA 4721 to New York JFK leaves the gate
4 h 44 apart on the timetable
Boston’s board gives an arrival time for only about 59% of its flights, so many days show no gate time.
The last days
AA 1225 and AA 4721 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.