AS 3166 then AS 310 at Seattle
Portland (Oregon) → Seattle → Denver
Timetable, Seattle time
13:19AS 3166 from Portland (Oregon) at the gate
18:59AS 310 to Denver leaves the gate
5 h 40 apart on the timetable
Seattle’s board gives a departure time for only about 59% of its flights, so many days show no gate time.
The last days
AS 3166 and AS 310 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.