You're not overlooking anything. It works the same way as Busse, if you're familiar with that at all. They release them in batches. What they'll usually do is post on their website forum, and maybe on here somewhere, that there's a new release coming out, with 48 hour and 24 hour notice, and then suddenly a message saying that it's go time or something like that. Then, they'll usually sell out quickly.
If you miss out on that, you have to keep an eye out on the secondary market, such as the for sale forum on this board or ebay, etc., and you'll probably pay a little more.
I got my Yard Guard from a guy on a well-known gun forum.