For the 3 of you who are likely to care

:
Like the US carriers, SA's Voyager program offers "MileageKeeper" and "AnyDay" awards where the latter are 2X the mileage of the former (but only 1.5X for local and regional flights) and are booked in Y, J and F so you can literally get the last seat on the plane.
Also "Companion" awards are booked in Y,J and F. The snag here is that the primary ticket must be issued in full fare Y, J or F.