Raid Testing Schedule for World of Warcraft Classic PTR

Blizzard has shared a Blue Post, confirming that they are still planning to begin Ulduar Raid Testing on Thursday December 8th and extending it an additional day to Wednesday December 14th.

Hello, just popping in for a quick update.
First off, wanted to let everyone know that barring us finding any major blocking bugs internally over the 24 hours, we are still planning to begin Ulduar Raid testing on Thursday Dec 8th. To help everyone prepare for this we plan to turn character copy back on tomorrow December 7th at or around 12 p.m. PDT.
Additionally, we plan to leave the raid available for an few extra days, likely letting it run until Wednesday Dec 14th so that guilds that raid earlier in the week have a chance to participate as well if they wish to do so.
As always, this could all change if something unforeseen pops up, but we are fairly confident that we’ll be in a good state for Ulduar testing on Thursday. We’ll post a more detailed update with build notes and known issues on Thursday shortly before the raid unlocks.
Thanks all and looking forward to seeing you on the PTR!