AA 581 then AA 1457 at O'Hare
Miami → Chicago → Boston
Timetable, Chicago time
09:30AA 581 from Miami at the gate
20:00AA 1457 to Boston leaves the gate
10 h 30 apart on the timetable
The last days
AA 581 and AA 1457 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.