Create firewall config to redirect standard router IP (192.168.1.1) to router no matter real LAN IP range
This is suppose to be optional feature (an in case of ~Firewall default) feature that just simply allows users to access router every time they tipe in this address.
The point is that this address is in documentation and even if user is informed about its change (because of collision with WAN address range for example) it might not remember and it might be ven confusing if instead of our interface, as they expected, they see interface of other (upstream) router (which is highly likely in case of WAN LAN IPs range collision).
This should be DNAT rule to firewall that changes destination IP address from 192.168.1.1
to actual LAN IP. This should work only if LAN has static IP.