Xperia 10 Plus a few questions!

[johna1954]

Hi Everyone, my first post on this comprehensive forum and I hope somebody out there can help or point me in the right direction.

I have recently purchased a used Xperia 10 Plus specifically with the 'Bootloader Unlock Allowed =Yes'

This Has Android version 10 installed after the previous user cleared out old files etc

My intention is to eventually install an alternative O/S (Sailfish)

Question:

Can I revert back, easily, to Android version 9  (Sailfish only works with 9) without affecting the 'Bootloader' option. I think this is factory set and cannot be changed but would like reassurance if possible. Would a Factory reset of the phone restore (or give the option) to install ver 9 or is there any other way to revert back to ver 9?

Thanks for any info you can give.

johna1954

[MarlonUk1]

hello @johna1954 

might I suggest heading on to XDA forums for more information regarding third party software modifications.

just remember unlocking the bootloader will void your warranty.

https://developer.sony.com/develop/open-devices/get-started/unlock-bootloader

[johna1954]

Thank you for your reply nolramlb,

I have seen that link regarding the bootloader and intend to follow its instructions in due course. My primary concern is the best way to revert the phone to Android 9 and ensure that the bootloader will still be able to be unlocked.

The phone I have is secondhand and came with no warranty, I understand the risks  which is why I am trying to minimise  them as much as possible.

John

[MarlonUk1]

Yes you would be able to revert back to previous Android version .. unofficially. You can just download it and reflash the previous version. Or if you have a back up.. 

[johna1954 · Accepted solution]

I managed to revert to Andriod 9 after installing EMMA on a Win 10 VM (would not install on Win 7, too old?). Sailfish installed, eventually, had trouble with USB in Fastboot, saw article re trying another socket, the one on side of monitor was the only one that worked.

Happy Sailfish now installed and having fun getting stuff to work no doubt be back here soon for more much appreciated help.

John