Microsoft says Windows 10 Anniversary Update is coming August 2

Confirmed]

The second major update to Windows 10, widely called the Anniversary Update, was introduced first by Microsoft at the Build conference in 2016. At that time, the Executive VP said that the Anniversary Update would be released this summer, although no date was provided by Microsoft.
Now, Microsoft Accidentally wrote a blog post with a headline only,tiledMicrosoft announces Windows 10 Anniversary Update available Aug. 2” (You can see the page here) and pulled the page moments later.However,it was too late that it wasn’t noticed by anyone.It’s possible that Microsoft just got the date wrong, but, more likely than not, Microsoft seems to have just clicked the publish button earlier than it meant to.Here is a related screenshot:
Capture

 update would be free to people running windows 10 already,but not for those who are running any less than 10 like 7,8 etc as the free offer ends 3 days before the accidentally released date.
Here is the change-log till now about what is new in Anniversary update:

[CHANGELOG TILL 14371]What is new in Anniversary update till now from Windows 10 v1511

Also,

All about Redstone-The next major upgrade to windows

Update 

 There is one more blog post written just now by Yusuf Mehdi, corporate Vice President of  MS confirming the release date to be 2nd Aug 2016.

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