UA 6327 then DL 2709 at Houston
Monterrey → Houston → Atlanta
Timetable, Houston time
12:30UA 6327 from Monterrey at the gate
08:05DL 2709 to Atlanta leaves the gate
19 h 35 apart on the timetable, overnight
DL 2709 leaves 19 h 35 after UA 6327 arrives on the timetable: more than half a day, so not a connection we count.