Microsoft announces Windows 10 Rollout for Lumia Phones from December

The Windows 10 Mobile build 10956 will be released in December. However, the Windows 10 Mobile build 10596 won't be releasing to all Lumia users and some Windows 8.1 Denim version users are unlikely to receive the update. Some of the Windows 8.1 denim devices will receive the Windows 10 update some time later.

While the Windows 10 Mobile build 10956 will be releasing on November 12, only select devices will be receive the update. Availability of updates will vary by carrier and country

According to Lumia Help, the Lumia 950 and Lumia 950 XL will ship with Windows 10. However, windows 10 update for a broad range of Lumia devices are likely to come some time later. Microsoft has given detailed information about the Lumia 10 software upgrade for India region here on its website.