It appears that the Dawn of the Infinite mega-dungeon testing will begin later today on the Dragonflight Patch 10.1.5 PTR, with Blizzard opening a new feedback thread for the activity!
Hello! Please use this thread for feedback and bug reports regarding the Dawn of the Infinite dungeon, or related issues. Noting the nature of your group and players (guild premade, PUG, role/spec) is helpful as are specific details about your experiences.
Thank you to everyone who has come out to help test!