AC/DC Is Up To Something. But What?

AC/DC is up to something based on some cryptic posts on social media in the past 24 hours. Yesterday the band posted a short video clip of an illuminated lightning bolt. And today this poster was spotted outside the former High School of Angus Young with the words "PWR/UP" and a link to a new website,

All signs are pointing to a new AC/DC album or song very soon.