I tend to the view, with rare exceptions, that the range owned by a company is monolithic: either broadband, servers or some other class. If a2b have mixed broadband in the midst of servers then it's for camouflage - hiding mines amongst the melons. In the case of a2b they KNOW what cyberbunker is so should in any case eject them. They are culpable.
In any case, NL is a major source of grief so serves them right. :)