The general sale for the BrickLink AFOL Designer Program is now live and you can purchase any of the 13 successfully crowdfunded designs of your choosing. The sale will last until June 30 so as of this writing, there are 28 days left to put your orders in. Technically there are 12 sets that you can readily order as the Löwenstein Castle has been sold out but you can join the waitlist.
Each set will come with an individually numbered sticker on the sleeve of the box as well as a some holographic stickers that make it feel more like a high end product. You can check out more of these details over on Brickset.