Apple appears to now be limiting access to the iWork for iCloud beta for select users. It was just last week that the company opened the beta to everyone, but now an "overwhelming response" is forcing the company to pull back.
The message in the image above is appearing for some users when they try to access the iWork for iCloud beta (whether it's Pages, Number, or Keynote). There's no word on when the limited access will be lifted, but Apple tells users to "check back soon." It's also important to note that restricted access to the beta does not affect a user's ability to store iWork documents in iCloud.