If I am not totally mistaken, a few months back, after he was asked about this, Grox already "leaked" in global chat, that there is "something to expect" until the end of the year, including a raise of the levelcap.
Since that was no official announcement, this information is as detailed as it can be and I am sure there will be an announcement when the time comes, just as there was for Gorge.
Until then I don't really care if I know any details about the instance or any date of release 2 weeks or 2-3 months beforehand. Whats the point of knowing that, if I already know that the new instance is coming?!
Inferno was there for about a year until Gorge was released and obviously Gorge was designed to last longer (also no Worldboss/Bossini for stats farming), until the community is "done" with that instance. If you think back, about three months before Gorge was released, way more poeple had a 2nd and maybe even a 3rd gear finished with inferno stats, now only very few poeple, reflecting in items and stats prices.
Furthermore and most important in my eyes, you should look at the majority of players and their activity when thinking about releasing new content, not only the few most active ones, who have run an instance for more than a year, at times multiple times each day. And as far as I know, there are some guilds who just started running Gorge regularly, so I doubt all those are already craving for a new instance.
Feel free to correct me if I am wrong there.
In the end my guess is, that Gorge and its items were designed to give the rather small dev team more time to focus on other stuff, what they obviously did, if you read the last years patchnotes.
So I am not surprised that the next content is taking as long as it does and if you are bored of Gorge because you spent too much time in there, what keeps you from doing other stuff and returning when there is new content?
Cheers!
Hello,
Like Melodic noticed, we designed Gorge this way in order to be able focus on other things that were waiting long, like ISS rework. As you might see, we always try keep our dev team as professional as possible. This year Byte joined to dev team, so we were able to start working on more tasks that were reported even 2 years ago. We focus firstly on general cleanup, and in meantime our game design department is preparing new content. Past months we were also busy with internal changes and also fighting with attacks on the game. Certainly, you can expect new content in following months, however it might be concerning different game aspects.
Greetings
I am very happy that you were focussing on "general cleanup, and ... game design".
I think Arcadia is in a very good shape right now.
But nevertheless from my perspective Gorge is lasting 1-2 months too long right now.
I really hope that the new instance is coming this month and that we will get a little bit smaller cycle regarding on new end content instances. Like 9 months with smaller instances.
Maybe a bit bigger than Tikal, but smaller than Gorge.
Keep continuing the good work. 
