AV 6975 then UA 1259 at San Francisco
Vancouver → San Francisco → Houston
Timetable, San Francisco time
16:06AV 6975 from Vancouver at the gate
10:53UA 1259 to Houston leaves the gatealso EK 6364, VA 8078, NZ 9197
18 h 47 apart on the timetable, overnight
UA 1259 leaves 18 h 47 after AV 6975 arrives on the timetable: more than half a day, so not a connection we count.