UA 4179 then AC 8908 at O'Hare
Roanoke → Chicago → Toronto Pearson
Timetable, Chicago time
07:44UA 4179 from Roanoke at the gate
20:40AC 8908 to Toronto Pearson leaves the gate
12 h 56 apart on the timetable
AC 8908 leaves 12 h 56 after UA 4179 arrives on the timetable: more than half a day, so not a connection we count.