It seems the Mage Tower will be going away for a while, as Blizzard have announced its removal when the pre-patch launches next week and its return after Dragonflight’s launch!
Mage Tower (Source)
We have some extra work to do on the Mage Tower Challenge to provide the best experience for those who are pursuing its rewards, so with the pre-expansion patch (10.0.0) next week, we’re going to disable the Mage Tower.
We hope to re-enable the Mage Tower soon after the launch of Dragonflight. We’ll let you know as soon as we can confirm a date for that.
For those of you who are close to completing a spec in the next few days – good luck!