UA 2617 then DL 2709 at Houston
New York LaGuardia → Houston → Atlanta
Timetable, Houston time
13:25UA 2617 from New York LaGuardia at the gate
08:05DL 2709 to Atlanta leaves the gate
18 h 40 apart on the timetable, overnight
DL 2709 leaves 18 h 40 after UA 2617 arrives on the timetable: more than half a day, so not a connection we count.