Windows Phone 8.1
Nokia Lumia 930 and Lumia 630 powered by Windows Phone 8.1. Nokia

The Windows Phone 8.1 update rollout schedule for Nokia's Lumia series smartphones has surfaced via a leaked roadmap.

Along with the announcement of Lumia 930, Lumia 630 and 635 at the 2014 Microsoft's Build Conference in April, Nokia confirmed that the Windows Phone 8.1 would be available for all Lumia Windows 8 smartphones as an over-the-air (OTA) update starting this summer. This includes Lumia 1520, Lumia 1020 and Lumia 520. Nokia then failed to provide a firm date for the rollout.

Now, evleaks has shared a leaked roadmap from Nokia through Twitter revealing the Windows Phone 8.1 update release schedule for the Lumia handsets, with a tweet that reads: "Schedule for rollout of Cyan—Nokia-specific Windows Phone 8.1."

The roadmap is for the Benelux region, but considering Nokia effects a rollout in most regions in a timely manner, the Windows Phone 8.1 release will not be much delayed and is expected to reach other regions around the similar time frame.

The handsets listed in the roadmap are Lumia 920, Lumia 820, Lumia 620, Lumia 520, Lumia 720, Lumia 925, Lumia 1020, Lumia 625, Lumia 1520 and Lumia 1320.

Besides, the update is expected to start rolling out sometime in July and will continue in August. The Lumia 930 and the Lumia 630 are the first smartphones to run the latest iteration of Windows Phone 8.

As Nokia mentioned, the Lumia series smartphones running Windows Phone 8 will get an OTA update, called Lumia Cyan, which will integrate the Windows Phone 8.1 and brand new Lumia features into one package.

This includes camera roll enhancements and Creative Studio, a new and an improved Nokia Storyteller app for sharing stories as a video slideshow on social networks.