Back to the orig question, vis a vis my 1st response, and that particular UK ins situ aside...
I would still go for tires with the orig index rating unless I was driving it solo or with just one
passenger, 95% of the time. I would not give that 106 vs 110 rating much of a huge concern,
if it was just driver with "no stuff".

We haul 4 people and lots of stuff frequently or, 2 people and really lots of stuff,
on trips, with regularity; if I was commuting solo, I would not sweat the diff.
GL,mD