I am not so sure re JNB. The A380 would have to be approved for the new EDTOP's [Extended Diversion Time Operations] which would not happen in a short time frame as it has not flown that route before. The same for EZE [Buneous Aires]. I think it would also apply to VAustralia if they were to consider these destinations, even more so only on 2 engines [B777].
The new legislation will require all new aircraft, regardless of the number of engines to meet & prove it's capability based on much more than an engine failure. Fire suppression etc is now considered more important. Aircraft that are currently flying will have grandfather rights & may continue to do so.