UA 3905 then UA 265 at Houston
Cancún → Houston → Pittsburgh
Timetable, Houston time
13:29UA 3905 from Cancún at the gate
07:40UA 265 to Pittsburgh leaves the gate
18 h 11 apart on the timetable, overnight
UA 265 leaves 18 h 11 after UA 3905 arrives on the timetable: more than half a day, so not a connection we count.