It was somewhere outside Barstow when Joe wrote:

In the process of having a new kitchen fitted, and being told the new
sink has to have 10mm bonding back to the CU. Is this correct?

No. There's no requirement to earth it, there is a requirement for
equipotential bonding. I suggest getting yourself an "on-site guide"
which explains the difference. They're more often confused than
they're correctly understood.

(Simply put, metal things need to be conected together, but they don't
need to be run back to the CU)