Here is why the Lumia 1020 (and likely other phones) are not getting Windows 10 Mobile

[Windows Central]

Yesterday, Microsoft finally began the process of rolling out Windows 10 Mobile in an official capacity for older Windows Phone 8.1 devices. In many ways, the Windows 10 Mobile era has now started.

Despite 18 phone models (see the full list here) being eligible for the upgrade there are plenty of older Lumias not getting the update too including any phone with 512 MB of RAM. Compared to Android Microsoft is another league (don't take my word, see what Hildenbrand thinks about the Windows 10 Mobile upgrade process at Android Central).

Full story from the WindowsCentral blog...