How to install Wi-Fi 6 Add-on to Mox?

As widely known, SDIO Wi-Fi card does not work anymore at Mox A since Turris OS 6. The support told me to downgrade to 5.4.4 and recommend to purchase Wi-Fi 6 Add-on. Of course I need Mox B to be able to plug it in.

Mox booted and shown this notification:

Your MOX HW configuration changed! You added moxtet-pci.0 module(s). Make sure that your setup is correct or try factory reset for new setup.

So what is the correct setup? I did not find it at Add-ons - Turris Documentation

Ok, it seems that unplug SDIO and upgrade to 6.0.3 could help.