B6 833 then UA 581 at San Francisco
Boston → San Francisco → Cleveland
Timetable, San Francisco time
13:16B6 833 from Boston at the gatealso FI 7969
12:45UA 581 to Cleveland leaves the gate
23 h 29 apart on the timetable, overnight
UA 581 leaves 23 h 29 after B6 833 arrives on the timetable: more than half a day, so not a connection we count.