DL 2879 then AA 1073 at O'Hare
Atlanta → Chicago → Buffalo
Timetable, Chicago time
19:05DL 2879 from Atlanta at the gate
19:00AA 1073 to Buffalo leaves the gate
23 h 55 apart on the timetable, overnight
AA 1073 leaves 23 h 55 after DL 2879 arrives on the timetable: more than half a day, so not a connection we count.