AA 3100 then UA 3919 at Houston
Miami → Houston → Newark
Timetable, Houston time
08:59AA 3100 from Miami at the gate
17:00UA 3919 to Newark leaves the gate
8 h 01 apart on the timetable
The last days
AA 3100 and UA 3919 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.