DL 456 then DL 2020 at Atlanta
Boston → Atlanta → Oklahoma City
Timetable, Atlanta time
11:58DL 456 from Boston at the gate
11:20DL 2020 to Oklahoma City leaves the gate
23 h 22 apart on the timetable, overnight
DL 2020 leaves 23 h 22 after DL 456 arrives on the timetable: more than half a day, so not a connection we count.