I fitted solar panels just at the point when billing agents changed their rules, I had an export meter fitted, but by time I came to register they were no longer accepted.
I also made a mistake, the installers said they would do all the work to get us set up with Scottish Power, but my wife has noted British Gas gave better rates, so decided she would do it all and use British Gas, in hindsight an error, so between delay getting smart meter, and being tied with British Gas for a year, it was 20 months before we got any payment for export, then moved to Octopus and within 2 weeks was being paid for export, British Gas had given us incorrect information telling us we had filled in forms in wrong format, it was their forms, the real reason was we needed a second MPAN number you have one for import and one for export even if using the same meter.
Again hindsight, since you do not need to export to same provider as one imports from, clearly would need two MPAN numbers.
The delay in getting smart meter was part down to the meter board having other stuff on it, and so not enough room for the smart meter.
Looking at this

I would not be supprised if they have the same problem here. They left me with the boxes the meters came in, to show the solar installers how much room is required, so the solar consumer unit has no lid on it, as tucked into corner of meter and CU box and would not be able to open lid, it would foul on the doors of the cupboard.
At least now I do not have meter readers call, and have to escort them into flat under main house where the meter is, which in winter down some slippery steps, was not really a good idea.
However now to read meter, I need to press buttons, it seems I want Rate 01 ImP, Rate 02 Imp and also a third for Export, but no amount of pressing buttons ever seems to display all, I have to rely on the Phone App to know how much I am using.
Since the solar software also tells me, at least I know it is not too far out, the two are never spot on the same, but near enough to know they are some where near correct.
But with a communal meter, all need to be able to read it, having unwanted info displayed like this

is not helpful when all you want is kWh used. Wonder if they would issue 4 IHD (in home display units) one for each flat? And also 4 or more apps active so all can see what is being used on their phones?