Luckily, if you're an Idiot Nation member, you can win a free copy of the album on CD. The official fan site is giving away five copies to members who enter on the website before the contest ends May 30th.
There hasn't yet been any word from the band regarding availability outside of Record Store Day sellers and Idiot Nation. With the popularity of this album so far and considering it's a release from Green Day, I think it's safe to assume it will eventually be released via a wider medium. If so, we will be sure to let you know.