315.70 tyres not rated at 7.5t

Someone knows there stuff!!
Yes, I had 4 tyres with a 152 rating.
Now I have a brand new pair that have 154.
The truck passed last year with the same tyres.
As the truck and tyres were supplied by the people testing the truck, I have told them it’s down to them.
Not sure if we are going to have an argument about that yet.
My point is, I’ve been running trucks for over 30 years, and didn’t think I needed to know this ■■■■.