UA 356 then DL 1564 at O'Hare
Phoenix → Chicago → Seattle (SEA)
Timetable, Chicago time
12:39UA 356 from Phoenix at the gate
12:00DL 1564 to Seattle (SEA) leaves the gate
23 h 21 apart on the timetable, overnight
DL 1564 leaves 23 h 21 after UA 356 arrives on the timetable: more than half a day, so not a connection we count.