Avenged Sevenfold wanted to capture the new release excitement by dropping theirs on fans from out of nowhere, by all means possible.

So, they didn't tell anyone "The Stage" was finished until it was already out! Keeping secrets these days is damn near impossible though so, M. Shadows explained how they did it to Forbes:

That was the difficult part. We had a bunch of smoke screen-type of scenarios that we were playing through our heads. We knew the days that certain corporate accounts were going to have to put it up on the internet, and even though we were able to take those down, we knew there would be some leakage on certain dates. One thing we did is we had Chris Jericho put up a post about a fake release date, and then he took it down, and we all knew really well that he would be looked at as the guy that blew it, like he blew the release date, so they all started printing that as if it was fact.

That gave A7X time to pull the real info and post false stuff. They even had fake Best Buy workers posting things like; "The release came today, and it's not out until December. Here's a picture of the box." Shadows added:

We had all these smoke screens up that took people’s attention away from the reality that the CD was unmarked sitting in their truck, or in the back of their store. It was pretty crazy that nothing leaked earlier, but there were a lot of things going on to hide the fact that it was there.

There's much more to the story, click here to read the rest.