Lumia 640 w10 upgrade

[sumon mia]

I bought lumia 640 at&t, then i unlocked my phone. Now i m using my phone in Bangladesh with a local carrier named AIRTEL.
Can i upgrade my phone to windows 10 by update advisor?
Plz help me

 

[RumoredNow]

Can i upgrade my phone to windows 10 by update advisor?

Not yet. Still waiting for AT&T to pass the upgrade... Rumor is it may be this month.


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 you can choose the Production Ring to un-enroll from Insider.

Check out this thread: Windows Insider Testing and You [Recommended Guidelines]

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?