Minibuses with more than 8 seats are restricted to 50 on S/C and 60 on D/C but on motorways they are not restricted and the normal 70mph applies. The Renault Trafic on the scheme has 9 seats so technically if a speed camera van caught you doing 70mph in this vehicle on a dual carriageway could you get a speeding fine?
There are second hand adapted vehicles and converted MPV’s that started life off as vans only for the driver getting issued with NIP’s because they didn’t realise the different speed limits for vans and cars. I suppose it is more to do with how it was first registered for the purpose of law and if you do get a NIP driving a VW transporter, Renault Trafic, Toyota PROACE Verso, Hyundai i800, Mercedes-Benz Vito etc. then you would have to prove it.