DL 1630 then UA 4500 at Detroit
Rochester → Detroit → Washington
Timetable, Detroit time
07:24DL 1630 from Rochester at the gate
19:45UA 4500 to Washington leaves the gate
12 h 21 apart on the timetable
UA 4500 leaves 12 h 21 after DL 1630 arrives on the timetable: more than half a day, so not a connection we count.