you might want to check the load rating of the Alloys too
i pinched this from T4 forum
to stay legal with tyres its simple..
load rating of tyre must be above half the axle loading on the chassis plate.
and must be speed rated above the max speed of the vehicle...
how much weight you put in your van and how fast you drive is irrelevant.
all they need to do on a roadside check is check chassis plate and read tyre sidewall.
neither speed rating or load rating of tyres are current MOT items on a passenger car or light goods vehicle but having under rated tyres is 3points per tyre thats illegal if you get stopped.