Hi, on some devices (e.g. Ubiquiti) it is possible to hide indorr channels or to define a list of frequencies the driver is allowed to chose from.
In openwrt you can select only one frequency or automatically all of them. Whereas DFS channels can be detected, we have some frequncies that are forbidden outside (country code AT)
Is there a way to allow 5500 Mhz to 5680MHz (+ DFS disabling) or to disable frequencies 5180 - 5320?
If not possible in Luci, perhaps ther is a way for a config with more than one frequency allowed?
Meanwhile found a thread that adresses (and answers) the question:
https://forum.openwrt.org/t/wi-fi-channel-auto-selection/47776
[note:
option channels '100 104 ...' did worked for me
option chanlist '100 104 ...' did not
Luci does not remove the additional line in /etc/config/wireless 
but there is no way to add or modify with luci
hw: TP-Link CPE510 v3.20
fw:OpenWrt SNAPSHOT r14551-e147b9d616 / LuCI Master git-20.305.72436-6e4e132]