LA 6139 then UA 863 at San Francisco
Boston → San Francisco → Sydney
Timetable, San Francisco time
23:58LA 6139 from Boston at the gate
23:05UA 863 to Sydney leaves the gatealso LX 3158, VA 8005, LH 9327, NZ 9863
23 h 07 apart on the timetable, overnight
UA 863 leaves 23 h 07 after LA 6139 arrives on the timetable: more than half a day, so not a connection we count.