DL 3678 then DL 849 at Seattle
Boise → Seattle → New York JFK
Timetable, Seattle time
13:00DL 3678 from Boise at the gate
15:48DL 849 to New York JFK leaves the gate
2 h 48 apart on the timetable
Seattle’s board gives a departure time for only about 56% of its flights, so many days show no gate time.
The last days
DL 3678 and DL 849 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.