@woziwrt so base on your script, I tried to create a GH worflow but it seems that it does not work at all.
I created alternative build way, where I use theirs script, but not for building but just to copy theirs patches in this workflow.
What I spotted in my build is... that 5GHz network does not work for DFS. Dunno if it is related to my workaround patch or recent changes in netifd - in your build it does not raise any issue, where in my is raising issue with "wrong argument". I will take a look when I have few minutes.