DL 1012 then DL 1174 at Atlanta
Memphis → Atlanta → Philadelphia
Timetable, Atlanta time
12:54DL 1012 from Memphis at the gate
20:15DL 1174 to Philadelphia leaves the gate
7 h 21 apart on the timetable
The last days
DL 1012 and DL 1174 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.