Re: OK....so it is now the middle of May.....any word on Windows 10 Mobile for the 640 with AT&T?
Not that I've heard...
If you use Insider on the Release Ring, the same version is fetched as the recent public Upgrade received by these phones (10.0.10586.xxx): Phones Eligible for Windows 10 Mobile Official.
If your phone is on the eligible list and you go Insider and stay on the Release ring you get the next public version early as Release ring in effect is the RTM. This will deliver the most stable Redstone builds to you earlier than OTA push with minimal risk. Or select Production to un-enroll your phone from Insiderand WaaS (Windows as a Service) will deliver future updates within Threshold to you without any Insider access required.
For right now, Windows Device Recovery Tool is only flashing 8.1 to models that did not launch with 10 so it is the way to revert if you don't care for W10M: How can I recover/reset/restore my phone software?
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