AC 8604 then AA 9782 at Boston
Montréal → Boston → Chicago O'Hare
Timetable, Boston time
09:48AC 8604 from Montréal at the gate
11:00AA 9782 to Chicago O'Hare leaves the gate
1 h 12 apart on the timetable
Boston’s board gives an arrival time for only about 59% of its flights, so many days show no gate time.
The last days
AC 8604 and AA 9782 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.