I have a general query you may be able to answer.
In the various houses I have lived in I have often been tempted to put in a larger or more modern CCU. E.g. one with MCBs rather than fuses.
What has stopped me is the apparent inability to disconnect the CCU tails from the preceding unit (meter, distribution block etc) as these are often sealed by wires crimped with lead seals.
I have assumed you are not allowed to break these seals. Is this correct?
My confusion is compounded as I understood that the tails to the CCU are the consumers responsibility, but here you cannot touch them as one end is sealed. If you cant break these seals, how can you safely isolate the CCU to fit a new one?
Many thanks in advance