UA 574 then AV 2352 at San Francisco
Boston → San Francisco → Burbank
Timetable, San Francisco time
12:49UA 574 from Boston at the gate
07:15AV 2352 to Burbank leaves the gate
18 h 26 apart on the timetable, overnight
AV 2352 leaves 18 h 26 after UA 574 arrives on the timetable: more than half a day, so not a connection we count.