WN 209 then UA 5262 at Denver
St Louis → Denver → Williston
Timetable, Denver time
18:50WN 209 from St Louis at the gate
14:50UA 5262 to Williston leaves the gate
20 h apart on the timetable, overnight
UA 5262 leaves 20 h after WN 209 arrives on the timetable: more than half a day, so not a connection we count.