I know about the South Africa Flag, but with Africa I only used the modern flags, due to the flags of African nations changing so often. However I am sure that South Africa can be the exception to this rule....
http://www.fotw.net/flags/za_old.html#28
In my research for flags, most African nations changed flags at least once every five years. Due to this huge amount of flags, to get this correct, a huge amount of events triggering this would be needed. It seemed a waste to have a flag change 10 or 20 times for a single nation during this scenario. However, since South Africa was/is the "most stable" African nation, in terms of flags, I'm sure it won't be too out of the ordinary to have them be the exception, with both a modern and pre-modern flag.
I suggest though that if South Africa recieves Apartheid events, that we set up the events to have the flag change, regardless of year, once Apartheid has been removed.
Edit: Ok ... I did 2 new versions of South Africa, one with and one without the shields in the middle of the flag, as seen in the link above. I also redid the North Korea flag cause ... I never liked my first run at it lol...