170,000 London homes will get letters in the next day or two, telling them they're in the next phase of 4G testing and offering telephone support for anyone who sees Freeview disappear on Monday.
The testing follows a 22,000-home trial in the Midlands, which went remarkably well, if you're a network operator worried about taking EastEnders off the air. In that test only 15 homes lost any reception, a result at800 - the outfit running the tests - hope to replicate across the boroughs of Greenwich, Lewisham, Southwark and Tower Hamlets next week.
We’re assured by At800, the brand adopted by Digital Mobile Spectrum Limited who were appointed by Ofcom to solve the problem, that it "has a team of professional aerial installers and testing units in the area that will respond to calls from viewers, visit addresses reporting problems and restore Freeview".
Those experiencing problems should call 0333 31 31 800, but only if they've had the letter as, "if you’ve not been contacted directly through the post, or you watch cable or satellite TV, any interference to your Freeview service is unlikely to be due to the 4G test".
The trials are intended to judge the scale of the problem, which won't become evident until the 4G networks start switching on at 800MHz over the summer. In most cases a simple filter will fix problems, but as no-one knows how many cases there'll be, no-one knows what "most cases" means, or how many households that leaves needing more-expensive solutions, which is what the trials are intended to find out.