Drive license for the Toyota Proace Medium 1.5

Hi,

I just discovered that the vehicle weight could be a problem for my driving license (B)........................................

I wonder if the Toyota Proace Medium 1.5 is one of those that overtakes 3.5 tons, let me explain:

Vehicle Gross Weight: ~2.6 tons (people, fuel + load)

Vehicle Kerb Weight: ~1.6 tons (I guess the Van empty)

We are nowhere close to 3.5 tons, I noticed the Vehicle Train Weight of ~4 tons in the Proace specs, but is this about the weight of pulling a Caravan for example? I don't think it has anything to do with the VGW, or maybe is the max allowed between payload and trailer.

Anyway, the Van has the sticker on the right side that says that the Van could go beyond 3.5 tons (in a few words), so, can I drive it?
I don't need to use any sort of trailer and I'd never exceed 2.6 tons of VGW, well unless I transport gold 😄 

I found something "official" here: https://assets.publishing.service.gov.uk/media/62876d2cd3bf7f1f4947d306/inf30-requirements-for-towing-trailers-in-great-britain.pdf

Motor vehicle with a MAM of up
to 3,500kg, no more than eight
passenger seats with or without
a trailer – weighing no more than
750kg.
•
As category B but with a trailer
weighing more than 750kg. The
total weight of the vehicle and
trailer together can’t weigh more
than 3,500kg.

My doubt is, can I drive it if I keep it below 3.5 tons in GVW? (I don't need a trailer and I won't even exceed 2 tons...)

Or I can't drive it just because this Van can go beyond 3.5 tons?

Beyond my interpretation of the regulations, can I phone the DVLA or some competent office to double-check if I can drive it with a B license?

Is anyone aware on how it works?