Microsoft’s new Windows 10 Mobile powered smartphones Lumia 950 and Lumia 950 XL have just been launched, alongside the Surface Book, Surface Pro 4 and the second generation version of the Band, among others. Meanwhile, the Windows 10 OS specific to PCs have been made available for quite some time now.

According to a latest report, other compatible Lumia handsets will start receiving the new OS firmware update by the end of this year.

The newly unveiled Lumia 950 and Lumia 950 XL will apparently hit the store shelves with Windows 10 out of the box in November, targeting the holiday season. Existing Lumia device owners, on the other hand, will be able to experience the powerful Windows 10 Mobile OS from December onwards, according to an official comment in Facebook.

This news was reportedly broken by Microsoft representatives in the form of a reply to a query on the official Lumia Facebook page. A Facebook user apparently asked Microsoft about the Windows 10 update for the Lumia 640 and Lumia 640 XL, released not long ago.

The comment reads: "It is our ambition to make an upgrade available for majority of Lumia smartphones running Windows Phone 8.1." The representative further added that “Broad availability of Windows 10 on other devices, including mobile phones, will begin rolling out in December.”

Meanwhile, it is worth noting that a total of 8 GB of internal storage capacity is a must in order to become eligible for the Windows 10 update. This also means that handsets like Microsoft Lumia 530 will not receive the update, GSM Arena reported.

According to Phone Arena, here is the first list of older Lumia smartphone that will be updated to Windows 10 Mobile over a period of time: Microsoft Lumia 930, Lumia 830, Lumia 735, Lumia 640 XL, Lumia 640, Lumia 540, Lumia 535, Lumia 532, Lumia 435 and Lumia 430.