DL 4036 then DL 3677 at Seattle
Redmond → Seattle → Spokane
Timetable, Seattle time
07:55DL 4036 from Redmond at the gate
19:51DL 3677 to Spokane leaves the gate
11 h 56 apart on the timetable
Seattle’s board gives a departure time for only about 57% of its flights, so many days show no gate time.
The last days
DL 4036 and DL 3677 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.