The PR stunt appears to have been repeated on Snapchat, YouTube, and the USA website, according to a schedule shared by USA on Twitter.
And it was a stunt, but it's a pretty great stunt that dovetails perfectly with the themes of the show. A show about a hacker having a secret "hack" airing of the premiere is completely on point. It strikes the perfect tone to tease fans and whip the lucky ones into a fervor days before the show is scheduled to return.
If you missed the secret airing, count down the hours to Wednesday's premiere by reading the show's Wikipedia page to understand the plot of Season 1 (it's ok, the cast had to do it too), then watch the Season 2 trailer and wait like the everyone else who missed this brief window into the future.