Just did a fresh install of OpenWrt 21.02.0-rc3 on a WRT1900 AC v1 previously running a Davidc502 build (OpenWrt SNAPSHOT r13059-9fac9168c6 / LuCI Master git-20.116.42735-f44ba48)
Path of install is as follows: Davidc502 build --> OEM -- > OpenWrt 21.02.0-rc3 Did NOT preserve any data between installs.
After configuring the new install everything seemed to be functioning except the Pi 3B+ will not connect / stay connected via WiFi via the onboard radio to the new install of OpenWrt on the WRT1900AC.
The Pi 3B+ constantly appears and then disappears in the Associated Stations list.
Have rebooted both the Pi3B+ and the WRT1900 AC several time.
I guess that this should prevent so-called "deauth" attacks, among other things, since these "frames" (commands) are unencrypted.
At least it will probably go in this direction.
at least that's how I suspect - but I don't know exactly!