UA 1970 then DL 6939 at San Francisco
Cleveland → San Francisco → Calgary
Timetable, San Francisco time
21:45UA 1970 from Cleveland at the gatealso VA 8489, NZ 9046, OZ 9526
16:40DL 6939 to Calgary leaves the gate
18 h 55 apart on the timetable, overnight
DL 6939 leaves 18 h 55 after UA 1970 arrives on the timetable: more than half a day, so not a connection we count.