For updating firmware of BL locked Mate 20 Pro an experimental method is available using HiSuite to latest firmwares. Windows only, no Mac.
Purpose of this is to bring the device up-to-date even when OTA upgrade is not available at a given time for a given region/carrier.
*** CAUTION: may break SafetyNet check, i.e. disable Google Pay, if firmware higher than intended for a given region is flashed ***
Hope it helps you.
Usage: unzip HSTool, run as standard user and follow prompts. No need to run HSTool under elevated Windows privileges, just the "hosts" file editing needs privileged access to the filesystem.
Successfully tested firmware list:
(All variants) 9.0.0.206 (
Changelog)
Some very useful information and additional firmware can be found in this great thread intended for BL unlocked devices:
https://forum.xda-developers.com/mate-20-pro/how-to/guide-manual-updating-firmware-t3893171
This method was launched in that thread so there are already many useful posts regarding it.
Cust partition (region) will stay original based on device oeminfo. C432 wil stay C432 after upgrade and so forth.
2019/03/01: Tested 9.0.0.206 - full SafetyNet pass with C432 Vodafone (EU).
2019/03/12: Tested 9.0.0.211, 213 - partial SafetyNet pass; ctsProfile mismatch C432 Vodafone (EU)
2019/03/13: Tested 9.0.0.222, 225 - partial SafetyNet pass; ctsProfile mismatch C432 Vodafone (EU)