Here is what they had to say:
We are running a 25% Off Sale for PAX Prime. Starting today, August 21st at 10 AM PDT (5 PM GMT) the game goes on sale on Steam Early Access. The sale is for 2 weeks. The sale will be running on our website shortly after the Steam Sale Starts.
Not able to make PAX to get some free swag? We will be giving away 7 Silver Packages. Between the 7 winners and the winners at PAX we will have a grand prize drawing for a $100 Amazon Gift Card.
You can visit the link to sign-up. It requires a name/email or a variety of social media sites can be used to login and you will have 1 entry in with a chance to add a few more. The contest ends September 1st, but we might have a few early bird keys to give away.
Source: Press Release