I ordered a Xiaomi Mi Router 4A 100M and got a Mi Router 4AC 100M (NOT gigabit) .
After several days of bricking, reflashing, down grading the firmware, installing virtual box and ubuntu and following @hoddy tutorials, I finally got to telnet into it and installed this version (@zorro I think):
OpenWrt 19.07.2 r10947-65030d81f3 / LuCI openwrt-19.07 branch git-20.057.55219-13dd17f
Now it seems to work fine --I can use the luci interface to make changes see stats etc.
I could not find an answer in the 1000 message long forum post on the 4A/gigabit. And I spent a lot of time trying. And learning a vast amount.