Alistar: headbutt AA returns???

So I've noticed something over the last week; I'm able to headbutt AA with Alistar again. Catch??? You have to buy the new item rapid fire cannon. But otherwise, yeah, you CAN AA after headbutt but it is way way way more difficult than before. I'd show you a picture or screenshot but unfortunately I don't have one so just try it out in a custom. BTW, this isn't into the wall AA. I know that is possible, i meant an in lane knocking them max distance away AA.