DL 8843 then DL 2138 at Atlanta
Washington → Atlanta → Portland (Maine)
Timetable, Atlanta time
02:39DL 8843 from Washington at the gate
20:59DL 2138 to Portland (Maine) leaves the gate
18 h 20 apart on the timetable
DL 2138 leaves 18 h 20 after DL 8843 arrives on the timetable: more than half a day, so not a connection we count.