UA 643 then UA 1769 at San Francisco
Las Vegas → San Francisco → Miami
Timetable, San Francisco time
07:44UA 643 from Las Vegas at the gatealso AC 5211, NH 7315, VA 8122, NZ 9237
23:20UA 1769 to Miami leaves the gatealso CM 2876, NZ 2925, AZ 4495, EK 6427, VA 8392
15 h 36 apart on the timetable
UA 1769 leaves 15 h 36 after UA 643 arrives on the timetable: more than half a day, so not a connection we count.