I was looking through the Game Masters page on the Wiki & found it to have changed from this morning, stating GMs Oceanus & Glaucus are now retired.
http://wiki.spiralknights.com/Game_Master
I don't see an Announcement nor have I seen any Topic discussing this.
If you look at the history, you can see that Gamemaster Clotho added that section hence it's going to be regarded as fact.
I don't recall there ever being an announcement of Andrzej Kapolka leaving the development crew and it's very rare that you'll see any game designer state in an announcement of '[Person] is retiring from [Game].' There are rare cases otherwise but it's nothing really new. Shame that some have left though.