Thanks Marius, this sounds promising. However, for some reason this does not work for me. When I send this message I get no response. It is of course possible that I've gotten the admin password wrong because none of the other commands for which the authentication is done by means of the admin password are working either. (The only ones that work currently are status and mobileon / mobileoff, for which I have changed the authentication method from admin password to serial.) I guess there is no possibility to remedy the situation remotely since the router isn't connected to a WAN, it is only connected to the mobile network and the mobile subscription does not provide a public IP address, so I believe there is no way to access the web admin UI remotely in my case.