There is a new reporting link for overweight vehicles using Benton Street in an illegal manner.
Regrettably the link indicates that responsibility for monitoring and enforcing (!) the illegal usage of the street has been transferred from Trading Standards to the Highways Network Management section at the Economy, Skills and Environment Department of Suffolk County Council.  The new link is
https://www.csduk.com/CSD/SCC/product.aspx?ProductID=PHGV01