QUOTE(keroll_unwar @ Jan 23 2018, 11:18 AM)
so, those with custom rom, how do u guys flash it back to china rom?
1. try apply for bootloader unlock - with the "unauthorised" rom, i am not sure if binding of your xiaomi account will be successful or not. but do try and let us know if it works. if you can bind the account and approval is given then all that is left is plug into mi unlock tool, and then they force you to wait 360hours, and unlock again after the countdown finishes. after successfully unlock bootloader, copy paste china rom into root folder, boot into recovery and flash from there.
or
2. use the testpoint method - the same way they forcefuly flash the "unauthorised" rom without unlocking bootloader, but this time you are flashing an authorised china rom. nobody has done this yet from what i read in miui forum, so again, do try and let us know if it works.
******edit******
when you say custom rom i had earlier assumed you were talking about those who had the "unauthorised" global rom bought from online sales site like aliexpress/ebay .
Now let's assume that you have a unit with the mi A1 ported rom (or any custom rom like lineageOS if it exists) and you want to revert back to china rom, chances are if you already have a custom rom in your phone that means the bootloader is already unlocked (for you to flash a custom in the first place), so what you need to do is just copy paste china rom into root folder, boot into recovery and flash from there. maybe you already replaced the stock recovery with TWRP even.
alternatively again, test-point method.
This post has been edited by andrewhtf: Jan 23 2018, 11:51 AM