UA 434 then CX 3171 at Houston
Seattle → Houston → Anchorage
Timetable, Houston time
20:19UA 434 from Seattle at the gate
17:58CX 3171 to Anchorage leaves the gate
21 h 39 apart on the timetable, overnight
CX 3171 leaves 21 h 39 after UA 434 arrives on the timetable: more than half a day, so not a connection we count.