AS 2129 then DL 2880 at Seattle
Calgary → Seattle → Las Vegas
Timetable, Seattle time
09:06AS 2129 from Calgary at the gate
12:18DL 2880 to Las Vegas leaves the gate
3 h 12 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
AS 2129 and DL 2880 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.