@
Philgr
From the display shown on your meter, it's clearly configured to record exported energy so the fact that it's not actually communing smartly will not prevent you installing solar and recording exported energy.
you would just need to take readings manually and submit them online,
Now, you say you have no mobile signal. On all networks or just some? Smart metering in the southern half of the UK uses communications over Telefonica (O2) networks, or on other providers where they participate in 'code sharing'. I.e services are provided by EE or Vodafone and O2 use their infrastructure.
Where I live in West Wales, both EE and Vodafone have shut down older 3g systems already and every smart meter in a ten mile radius of the old masts no longer works. The 3g networks will all be completely turned off by 2032, but many providers are already shutting off as the demand for 3g services is so low. Only Telefonica will carry on right up to the deadline, but that is only where they own the infrastructure. If they 'borrow' other suppliers masts, then they have no control.
So, if you have O2 signal, your meter 'should' work. If not, it likely never will until the 'peer to peer' mesh system has been fully rolled out. Your hub doesn't appear to be 'mesh capable' so I'm willing to bet you will never be 'smart', without a complete refit.