UA 1850 then DL 3764 at Vancouver
Los Angeles → Vancouver → Seattle (SEA)
Timetable, Vancouver time
12:30UA 1850 from Los Angeles at the gate
08:26DL 3764 to Seattle (SEA) leaves the gate
19 h 56 apart on the timetable, overnight
DL 3764 leaves 19 h 56 after UA 1850 arrives on the timetable: more than half a day, so not a connection we count.