A few days ago, the official @LumiaIndia Twitter account outed August 9 as the release date of the Anniversary Update for Windows 10 Mobile. Seeing that the tweet was promptly deleted, nothing could be said for sure about it at the time.
However, a new report has now emerged claiming that the Anniversary Update for Windows 10 Mobile will indeed begin to roll out for the "open market" on the aforementioned date, and one week later for carriers.
As reported by Windows Central, the Anniversary Update will begin to roll out for unlocked Lumias, and Windows phones from other vendors, such as NuAns, Acer and more, this Tuesday. On the other hand, carrier-locked devices will be able to receive the update the following week, on August 16. This gives carriers more time to test the update before they approve it.
It is also important to note that these dates can obviously change, particularly since Microsoft itself hasn't officially confirmed them. The report also claims that preview build 14393.10 could be the one to be pushed to eligible handsets when the Anniversary Update rolls out.
Source: Windows Central