UA 273 then DL 2709 at Houston
Santa Ana → Houston → Atlanta
Timetable, Houston time
13:20UA 273 from Santa Ana at the gate
08:05DL 2709 to Atlanta leaves the gate
18 h 45 apart on the timetable, overnight
DL 2709 leaves 18 h 45 after UA 273 arrives on the timetable: more than half a day, so not a connection we count.