TN-C-C

Thus I think this just a simple misprint of the label probably purchase on Temu or similar by an Admin person who did not check what was delivered.  Occam's razor.

Got to be a misprint, labelling error surely

That would be my first guess too - should read TN-C-S (after all the DNO supply separate N and PE terminals - so the split happens on their side).

   - Andy.

Is it something to do with 80A at 415V ?

That's quite a normal specification for DNO equipment - the same modules can be arranged side-by-side to form a 3-phase cut-out (with 400V, 415V or 433V between lines, depending on your age and attitude to "nominal" voltage definitions).

   - Andy.

Hi, Got to be a misprint, labelling error surely ?

Is it something to do with 80A at 415V ?

Well the wiring on the DNO side of  that thing is (clearly!) TNC, maybe  with multiple NE interconnections (probably electrodes) ahead of it.

Anything downstream of that G/Y will be TNCC-s, which for our purposes is handled as  plain TNC-s.

As opposed to a DNO network with TNSCS or something where a former TNS supply has been patched in the middle with a section of combined neutral and earth at the joints.

I'm not sure if its a typo or they are really being more descriptive of their upstream network.
My money is perhaps more on a typo. 
Note that internal DNO speak often refers to CNE (combined neutral earth) and SNE (separated neutral and earth) rather than using the TN-x format that the international standards and BSI adopt. 
Mike.

Ah! I see. Thank you.

The insulated and sheathed tails are oversleeved where they go into the meter.

I spy with my little eye - some basic insulation in the meter tails. (The wrap of "L" tapes does not count.)