Hello,
I want to use additional channels when setting up the 5 GHz network on my Beryl but those are not in the list.
There is no settings at admin panel as well as on LuCI.
Maybe the region it set to US and I am in the EU?
Can you help me?
You need to do it from the shell (ssh) as long as the hardware supports it.
https://openwrt.org/docs/guide-user/network/wifi/basic
Last section (DFS detection) can be helpful to your case
There are two ways to modify the wifi channel, or modify the 5G country code in MTK wifi