When Google announced YouTube Music Key, we had a few questions, most of which revolved around how this would affect Google Play Music All Access subscribers. Music Key's inclusion of All Access was part of the announcement, but it wasn't stated whether or not AA subscribers would automatically get access to Music Key, or if they'd have to sign up for the service all over again. Of course, that would be a really stupid way to handle things, so thankfully Google isn't doing that.
It turns out the Google is handling this in the best way possible, and making it a seamless transition for current AA members. Another bit of takeaway from the above image is the timeline: it looks like we could start seeing Music Key beta roll out to AA members as early as next week.
Thanks, Marco Duran!