UPDATE: It's online for some servers (e.g. EU-Blackrock)! The currently ongoing rolling restarts are most likely connected to the unlocking of the scenario.
Hey guys, just a quick heads up: The Theramore scenario will open a tad bit earlier than originally expected. Depending on the timezone, it will open up in the next few hours (EU gets it first, according to Bashiok's tweets (https://twitter.com/Bashiok). Forum rumors currently seem to point towards an 18:00 opening in each timezone, since "afternoon" was the aim and 17:00 has passed in gmt+1 timezone. Obviously it's blizzard and things may change on short notice. The original bluepost, now edited to say 17-25 sept. instead of 18-25: Theramore's Fall: One Week at Level 85 - Forums - World of Warcraft (originally, it said 18th sept: MMO-Champion - Battle of Theramore: One Week at Level 85)
So if you've been waiting for the scenario like I have been, you might want to hurry as it could open any hour, depending on where you live.