As expected, there are some extremely knowledgeable posters on here and I am always learning from the wisdom of others. I had hoped that adding a second charge point inside my garage would be made easier following the installation of the first, but it seems that will not be the case. My existing Tesla WC is fed from a mini consumer unit in the garage that is cabled to the house consumer unit via a 40A breaker. The cabling from house to garage looks very robust, thick and shielded. I had hoped to be able to add another Tesla WC in the master/slave configuration and rely that used together they would never pull more than 32A. It sounds like the diversity rules will disregard this (and I suppose I can understand the concern). So will a priority board potentially solve this?
Yes, a priority board will fix this. Cost is around £125, plus installation.