Blizzard has shared a Blue Post explaining that the Burning Crusade Classic PTR will be going down today and return at a later date this week for further testing.
We’ve gotten a lot of useful data so far, and we need to work through it and fix some issues that have come up, so we’re going to shut down the 2.5.3 PTR at 4:00 p.m. PST today.We expect to bring it back up for further testing next week. Thank you very much for your testing and feedback thus far..
Read more on wowhead.com