AA 2363 then AA 1812 at O'Hare
Denver → Chicago → Miami
Timetable, Chicago time
16:00AA 2363 from Denver at the gate
16:43AA 1812 to Miami leaves the gate
43 min apart on the timetable
The last days
AA 2363 and AA 1812 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.