It wasn't. This was part of a planned update and was pretty clearly mentioned in the patch notes as a thing.
Unlike Nutaku, bugs don't survive long on DMM and compensation always follows, even for the most minute things.
Not to mention the fact that they refunded FGems to anyone who purchased additional Storage space, before the update hit.
The fact we had to wait for several month for Nutaku to even give us those 200 slots. And While I cant be 100% but I am on 99% sure they wont be refunding those FGems we burned to increase the storage.
The Leadership in Nutaku has changed and lately there have been improvements seen, but I don't think this is something we can count on happening.