DL 1223 then DL 659 at Atlanta
Cincinnati Northern Kentucky → Atlanta → Las Vegas
Timetable, Atlanta time
16:33DL 1223 from Cincinnati Northern Kentucky at the gate
15:59DL 659 to Las Vegas leaves the gate
23 h 26 apart on the timetable, overnight
DL 659 leaves 23 h 26 after DL 1223 arrives on the timetable: more than half a day, so not a connection we count.