That's why the postcode checker is useless. Many postcodes are served by a few cabinets located around it and also covering neighbouring codes. That checker only reports the first in the database.
if you enter only the postcode into the address option and press "Submit" or whatever, you will get a dropdown of all addresses in the postcode.
If you click on each in turn you will see the cabinet numbers (on the line above the table) are not all the same and some like you will have VDSL2 available and others not. Usually but not always, all those on a common cabinet will be enabled. But sometimes a address on that cabinet will be too far from it.
Kindness isn't going to cure the world of all its awfulness but it's a good place to begin. Daisy Ridley.
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