DL 706 then DL 2857 at Atlanta
Denver → Atlanta → Harrisburg
Timetable, Atlanta time
18:01DL 706 from Denver at the gate
15:47DL 2857 to Harrisburg leaves the gate
21 h 46 apart on the timetable, overnight
DL 2857 leaves 21 h 46 after DL 706 arrives on the timetable: more than half a day, so not a connection we count.