Client updates are independent of content updates. The above post is right, it's merely to make Graal compatible with iOS8. However a lot of players actually don't identify(despite being told it's important to maintain their progress) and they could lose access to their account when the client is updated. That is why an announcement was made.
Long ago when I played for a lil in 2010 lost all my stuff because I thought the verify was a scam
You run around graal and collect stuff and then turn it in hoping for a prize. Except for Haloween you have a chance of losing all your candy and not getting a prize at all and you have 1000 people going after the same ghost.