Lego is 20% off, and as well there are a few introductory offers instore for the new Avengers sets. That is probably why Lego is excluded from the 10% offer.
If I am not mistaken after glancing at the sale signs the 20% off lasts till 26/04. That sounds like a long time maybe I read it wrong.
I don't think we will see Wave 2 until May somehow.
I spoke to someone in Myer toy department and they told me that wave 2 was a wrong scan. And that they are still ordering from Hasbro. Hence, we won't be seeing wave 2 for a while.