Celebrations Pre-Orders are going to be released periodically, this is so all of our stock isn't sold out in one day, and we can keep releasing stock every so often towards the release.
We are just waiting for allocations on this set at the moment before we can list these for sale, we would hate to oversell on this set.
If the products are showing as out of stock, do not panic. They will be going back in stock. We recommend signing up to the back in stock email notifications which you can find on the product page. This will send you an email as soon as the product goes back in stock so you do not miss the restock.