Quote Originally Posted by aesteval View Post
Where is this info about the Diadem closing coming from? I haven't seen anything saying that.
Was in a live letter: http://forum.square-enix.com/ffxiv/threads/312514

The new exploratory mission is scheduled for release in the Patch 3.5x series. Players will not be able to enter the current exploratory mission post 3.5, so we ask you to please wait until this new exploratory mission is added.
The live letter says the current achievements will be obtainable in the new version. I imagine they'll make the crafting mats, Pegasus, and Hunting Hawk available there too.