Equivalent to Assign WAN port to switch on LEDE

So on DD-WRT​, Assign WAN port to switch makes a router a 5 port switch. It still has an IP address but the devices behind it just get handed off to the main one.

I tried to do something similar in LEDE yesterday but failed hard. I ended up locking myself out of the router by setting br-lan as a DHCP client.

Anyways, is there an easy way to do the same thing in LEDE?

Go to the switch vlan page and set the port in the wan vlan to disabled and in the lan vlan to untagged. Leave the cpu ports as-is (both tagged).

DHCP is still enabled though, right?

Yes, but it will be connected to nothing.

I meant DNSMasq handing out DHCP leases.

Yes, dnsmasq will still attempt to hand out DHCP.

Yeah this is non functional. As soon as I change the IP address to 192.168.1.254 and disable DHCP, everything stops working.

edit: turns out it was an IP address conflict with a broken managed switch. Fixed.