AA 1716 then AA 2284 at Miami
St Louis → Miami → Austin
Timetable, Miami time
08:49AA 1716 from St Louis at the gate
09:40AA 2284 to Austin leaves the gate
51 min apart on the timetable
The last days
AA 1716 and AA 2284 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.