This will date me as well , but here we go:

In around 1976/7 I flew on SA to LHR with a stop in Salisbury (HRE now, of course). That was a 747-200, I still have a picture I took whilst on the gound there. My memory is very vague about any other stop(s). The European airlines (KL) made a stop in NBO, also in the '80's.

Later the SA stops were in SID, with the deplaning (on occasion) and the hot and dirty 'hangar' where souvenirs were sold.

Then, and it must have been when the 747-400's came into service, it was possible to fly around the bulge non-stop. I was on the first flight that was rather suddenly alowed to fly over the bulge again (so that must have been in 1990/1). We did not know that this was going to happen. I remember leaving JNB late and being concerned that I would not make my connection in LHR. We were then woken up by the captain, telling us that during the night things had changed, we were allowed to overfly the bulge and we would be arriving at LHR 2 hours early! That was a major bonus to me!