AZ 4402 then UA 3906 at San Francisco
San Diego → San Francisco → Washington
Timetable, San Francisco time
09:20AZ 4402 from San Diego at the gate
07:00UA 3906 to Washington leaves the gate
21 h 40 apart on the timetable, overnight
UA 3906 leaves 21 h 40 after AZ 4402 arrives on the timetable: more than half a day, so not a connection we count.