OK, I had Global version with Global 10.0.1.0 ROM. I unlocked BL after 30 days, installed TWRP 3.2.3 from this forum and then flashed Magisk v.17. to obtain root access. On the other hand, as I later never had the need to boot to TWRP again, it is also possible that the custom TWRP really was overwritten, I can check out later can I actually boot into TWRP from system.
Have the same global version.. installed TWRP with no problem. installed magisk and after reboot i got bootloop (did try about 10 times and with no luck).