How does someone have the new seasons PvP neck when the new BH boss isn't out yet? link inside.

I don't understand:

http://us.battle.net/wow/en/character/stormrage/Sathrago/advanced

He has Cataclysmic Gladiator's Pendant of Diffusion already, which I am very confused by. The new season pvp gear isn't out yet, and the new BH boss has yet to be released.

Can anyone explain this to me?

Thanks.