UK communications regulator Ofcom has announced strengthened industry ‘guidance’ that it hopes will block more overseas calls. Ofcom is calling for evidence regarding the viability of new technologies to tackle the problem, and given that Hiya has a foot in the door via two of the big four UK operators, it is hoping that its spam detection and call screening services could be of use to the other two. EE (BT) and VMO2 (Liberty Global and Telefonica) are the two Hiya customers, and in short order, the other two MNOs may well merge into one – as the Vodafone and Three deal winds its way through the Competition and Markets Authority (CMA). EE says it is already blocking a million…