How to flash Pie sGSI in Mi A1

1.Enable Developer options in Settings app
2. Check Enable OEM Unlocking
3. Reboot to fastboot mode
4.Unlock your bootloader
5. Install TWRP-fastboot only through fastboot boot command (Extract the .img file from the zip)
6. Flash CosmicDan's TWRP Installer through your current TWRP.
7. Reboot to TWRP recovery
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8. Go to WIPE then ADVANCED then click FORMAT data. This will remove Encryption on your device and allows you to set new passwords when installing the GSI. Note that this will format your internal storage.
9. Treblelize through TWRP Tissot Manager (Go to advanced, click Tissot Manager and choose the repartition userdata option. Select singleboot option then click repartition)
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10. Flash latest Vendor.img as Vendor Image
10.1 Check if Vendor is mounted
11. Flash PQ3A.190801.002.img as system Image
12. Flash POST-sGSI 1 tissot zip.
13. Flash POST-sGSI 2 tissot zip.
14. Flash a treble-compatible kernel (Moun, Extreme, Canting)
14.1 Check in Tissot Manager / Patches if SeLinux is in permissive mode, if not, change and reboot to recovery
15. Reboot to system.

16. Once booted, install the latest Play services linked above either via the Files app or via adb (adb install apkname.apk). This will fix the Pixel Setup and Google Backup issues as well as allows you access to the Play Store without problems.
17. You can now flash Magisk 18.1 This is the stable version that works properly with treble.
18. Install the Data transfer tool APK update as well

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