Yes that is correct - you would still have the same number of shares (unless of course there was some sort of stock split announced) and those shares would now be held on the US exchange. How they show up in your holdings will be dependent on your broker. I am with RBC Direct Investing, and for me, those shares would no longer show up in my CAD account, but would now show up in my USD Account. Brokers do have different ways though, so it may not be the same for you.
In essence however, you still own your shares. You could contact your broker to see how they handled it. I see that the date has already passed, so i'm assuming you have AUPH shares in USD now? That would make sense. If you still have AUP in CAD, I'd contact your broker.
Mat