Windows 10 Mobile started to roll out to selected Windows Phone 8.1 devices earlier in March. If you upgraded your device to Windows 10 Mobile, but aren't happy with the newly released operating system, you will be able to easily switch back to Windows Phone 8.1 "indefinitely."
Downgrade Windows 10 Mobile to Windows Phone 8.1
The latest mobile operating system offering from Microsoft isn't available to many. Microsoft has confirmed that it won't be adding any new devices to the list of supported Windows 10 Mobile devices. If you are one of the lucky few who received the OTA notification to upgrade to Windows 10 Mobile, we hope that you are enjoying the new operating system. However, the mobile OS is still in development and Microsoft made it clear at its Build 2016 conference that mobile is not one of its priorities this year.
Not liking the newly released Windows 10 Mobile on your own smartphone? Jason, a member of the Windows Insider Engineering team, confirmed on Twitter that users will be able to downgrade Windows 10 Mobile to Windows Phone 8.1 and that they will continue to have this option to go back to their previous OS.
@GabeAul For a Retail user going from 8.1 to 10 who may hit an issue and need to recover, they need an 8.1 image to recover to.
— Jason (@NorthFaceHiker) April 4, 2016
Following Apple's strategy, it was initially believed that Microsoft may not offer the ability to go back to an earlier version of the mobile OS, due to security reasons. However, as Windows 10 Mobile is yet to be polished to offer full and stable functionality, it is wise to offer users to downgrade Windows 10 Mobile to Windows Phone 8.1. This might also help the company in getting more people on board the new operating system, as they won't have to worry about being stuck with an OS they don't end up liking.
If you too are unsatisfied with Windows 10 Mobile on your Windows phone, you can use Windows Device Recovery tool to flash a Windows Phone 8.1 recovery image to go back to the earlier OS.