No official news post that I've seen yet, but the TBC Anniversary PTR is now up! There are level 60 template characters that start with tier 1.

 Blizzard Entertainment

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Please note that in the 2.5.5 PTR, when copying a character from a live realm, all live realms (Anniversary, Era, Hardcore, Season of Discovery) will appear to be available. Nonetheless, it is not possible to copy a character from any realm other than a non-Hardcore Anniversary realm to the 2.5.5 PTR.

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