AA 548 then AA 1551 at Charlotte
Jacksonville → Charlotte → Philadelphia
Timetable, Charlotte time
10:03AA 548 from Jacksonville at the gate
15:02AA 1551 to Philadelphia leaves the gate
4 h 59 apart on the timetable
The last days
AA 548 and AA 1551 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.