If you are using standard openwrt br-lan interface config you probably also have to change the lan interface to br-lan.10 before you save and apply. Otherwise you will lock yourself out.
If you are experimenting with vlans (and only have 2 physical ports) it‘s always handy if you create a dedicated wlan management interface (in a different subnet) so you can always connect to the router via wifi in case you lock yourself out.
Yea you can do it either way but I think when using bridge VLAN filtering you have to reassign your LAN Interface to one of the bridge vlan devices you created. Otherwise, you will lock yourself out. At least I did.
If you only have have 2 physical ports (1 lan + 1 wan) and wifi only for management I think you don’t actually need a bridge (br-lan).
I would suggest changing br-lan to eth0 and then create a separate vlan(s):
Interfaces -> LAN -> change device to eth0
Devices/Add Device Configuration -> Create a new VLAN (802.1q)
Multiple bridges won't properly share the hardware switch between bridges, which is necessary if you have a "trunk" Ethernet port operating tagged packets on multiple networks.
The most generic way to set up is to make a bridge containing all the Ethernet ports, then have bridge-vlans within that bridge.
If your use of VLANs is very limited, such as having to tag packets on the WAN port for your ISP modem, it is possible to cheat and just use the notation option device 'wan.100' in the wan network. But this is a special case that doesn't expand to general usage.
The use case is actual VLAN support via a trunk to support multiple seggregated WLANs + having one specific port be in the ISP LAN for a TV set-top box. I'm going to experiment with your advice and see if I can make this work.