Normally it doesn't matter with this method if you are rooted. But to be sure, you can:
First flashing Magisk Uninstaller with TWRP:
It uninstalls also your modules.
After reboot your device.
Then flash HuRUpdater (from same folder on external SD where you have stored the firmware zip files. If you copy into same folder twrp.img and rename it: recovery.img - TWRP will be flashed together)
I received your PM and will answer later.
Thank you for replying. I have just run the HuRUpdater updater, about 10 mins ago. As you said it, it was a 'breeze' - I was fortunate not to run into any issues. I was dying, waiting for the new version to be released, and I said, the heck with it! Actually what I did was to prove is OTA update will fail, I executed the update. And phone restarted, and went to recovery. So I said, I'm already in the menu, and I have already prepared the files and all, so I installed HuRUpdater.zip, and it did the update for me.
I will keep that link you gave so I will have the chance to try it in the future. Now my Mate 10 is in .132(C636) build. I have once again flashed Magisk, and my phone is re-rooted.
Thank you for all the help.