yes i see that now,
the snapshot is still under construction so i brought a working vlan switch just to make sure i get a response. thanks to Adrian Schmutzler he's busy with the DSA system for the mt7621 https://git.openwrt.org/?p=openwrt/openwrt.git;a=commit;h=1eac573b530425c80c046eaa0b373b5e63d92451
thanks for all the help 
and the patience <3
Just one quick question left.
I have 3 the same routers redmi 2100 openwrt.
the first one is the main router and the other 2 are connected to the first router and setup as dumb ap.
has wpad-mesh any purpose because everything is connected trough lan a lan cable?
or is wpad-mesh more like aimesh from asus?
my experience with the same ssid's on ap's is always dropping connection or shifting from radio0 to radio1 and back without a reason 
and if i setup the routers as dumbap's so the gateway is the same as the main router and the static ip addres wil be a outside the dhcp range of the main router. how can i reach luci from the dumbap's ?
That is normal if the signal is better on the other band. But anyway this is a decision of the the client mostly, unless you are using some kind of band steering.
I don't understand where is the problem. If the main router has IP 192.168.1.1/24 and the dumbAPs 192.168.1.2 and .3 with dhcp pool .100-150 there is no issue.