You can force ita's hand, it is a bit more expensive, but earns miles
BMI has an YVR-LHR-CPT fare
Vancouver (YVR) to Cape Town (CPT) - dim., févr. 5
Vancouver (YVR) to London (LHR) - dim., févr. 5
BMI 4854 Dep: 6:15PM Arr: 11:50AM 9h 35m Airbus A330 Coach (L)
OPERATED BY AIR CANADA Layover in LHR lun., févr. 6 8h 15m
London (LHR) to Cape Town (CPT) - lun., févr. 6
BMI 2511 Dep: 8:05PM Arr: 10:20AM 12h 15m Airbus A330 Coach (S)
OPERATED BY SOUTH AFRICAN AIRWAYS mar., févr. 7
Cape Town (CPT) to Vancouver (YVR) - dim., févr. 12
Cape Town (CPT) to London (LHR) - dim., févr. 12
BMI 2510 Dep: 8:20PM Arr: 6:55AM 12h 35m Airbus A330 Coach (S)
OPERATED BY SOUTH AFRICAN AIRWAYS Layover in LHR lun., févr. 13 7h 30m
London (LHR) to Vancouver (YVR) - lun., févr. 13
BMI 4855 Dep: 2:25PM Arr: 4:25PM 10h 0m Airbus A330 Coach (L)