Funny you bring this up.
I received the offer back in April as well, and I booked two separate trips under the offer, both in Business (so Y status credit earn).
For flights I took on 30 April I called in early June to follow up on the credits and was told I hadn't registered for the offer online (which I had, and still had the confirmation email to confirm). The issue was fixed and I was told the flights would credit in a few days. I called again on June 20th and the credits appeared in my account 3 days later.
Second set of flights were taken on 19 July, with my father on the same booking so he could get the SCs as well (as per the terms of the offer).
Again it took several calls to Qantas between mid-August and mid-September to get the credits allocated - each time I was told they'd been re-sent for processing but nothing happened. The rep that helped me on Tuesday this week actually went away, arranged the credits and called me back later that afternoon to confirm.
My father, on the other hand, is still waiting for his credits. I suggested he call QF the same afternoon that my credits came through - he did and the call centre operator advised that because the flights were Classic Awards he would not earn any points or status credits. He mentioned my booking, even had the operator look up my account to see the credits for the exact same flights under the exact same promotion, but she didn't budge.
I've asked him to follow up again tomorrow, armed this time with the copy of the email Terms & Conditions from the original offer.
So whilst this was a very nice offer from Qantas, it seems the IT systems aren't geared up to automatically allocate the SCs and the call centre staff aren't very well trained about the presence of the offer, let alone how to apply the credits when required.