AS 684 then WN 988 at Denver
Portland (Oregon) → Denver → Buffalo
Timetable, Denver time
14:27AS 684 from Portland (Oregon) at the gate
11:50WN 988 to Buffalo leaves the gate
21 h 23 apart on the timetable, overnight
WN 988 leaves 21 h 23 after AS 684 arrives on the timetable: more than half a day, so not a connection we count.