UA 3874 then DL 1306 at O'Hare
Chicago Rockford → Chicago → Minneapolis
Timetable, Chicago time
01:21UA 3874 from Chicago Rockford at the gate
17:42DL 1306 to Minneapolis leaves the gate
16 h 21 apart on the timetable
DL 1306 leaves 16 h 21 after UA 3874 arrives on the timetable: more than half a day, so not a connection we count.