Hi Claire & Owen,
ive just been through this process...
I originally did the academic IELTS because l was thinking of sponsership and they required 7, I do have a British passport, however, I needed 8's for points purposes as I'm old! But I struggled getting the 8's, I kept missing it by 0.5! So a couple of weeks ago l sat the general and got 9's and a 8.5 so l was so relieved.
I also got got my positive skills assessment through AIR last week, it did take 22 weeks so prepare for a wait. I do have a British degree in Oncology & Radiotherpy Technology, so not sure how your diploma works from South Africa. You mentioned the nurses having diplomas and being accepted for degrees in OZ, that hasn't been the case recently as they have just changed the rules. I would be inclined to drop AIR an email to clarify, I found them very approachable. Your right regarding the points l have gained 15 points for this.
I submitted my EOI yesterday so l guess it's now the waiting game to be invited, I'm going for the 189 visa. If l can offer you any help please feel free to get in contact.
Jules