UA 4535 then DL 2709 at Houston
Huntsville → Houston → Atlanta
Timetable, Houston time
13:17UA 4535 from Huntsville at the gate
08:05DL 2709 to Atlanta leaves the gate
18 h 48 apart on the timetable, overnight
DL 2709 leaves 18 h 48 after UA 4535 arrives on the timetable: more than half a day, so not a connection we count.