F9 2021 then DL 4880 at Detroit
Philadelphia → Detroit → Grand Rapids
Timetable, Detroit time
00:05F9 2021 from Philadelphia at the gate
22:55DL 4880 to Grand Rapids leaves the gate
22 h 50 apart on the timetable
DL 4880 leaves 22 h 50 after F9 2021 arrives on the timetable: more than half a day, so not a connection we count.