AA 3308 then AA 1270 at Boston
Philadelphia → Boston → Charlotte
Timetable, Boston time
09:39AA 3308 from Philadelphia at the gate
12:57AA 1270 to Charlotte leaves the gate
3 h 18 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 3308 and AA 1270 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.