DL 2816 then DL 796 at O'Hare
Boston → Chicago → Atlanta
Timetable, Chicago time
14:05DL 2816 from Boston at the gate
15:00DL 796 to Atlanta leaves the gate
55 min apart on the timetable
The last days
DL 2816 and DL 796 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.