Not a good result from the technician unfortunately. We were pointedly asked while booking the appointment if ceiling access was available (which it was and confirmed as such) but the technician claimed on site that he was not legally allowed to enter the roof space. We feel that if he was legally not allowed to work in the roof space we should have been informed at the time of booking as the range extender unit is ceiling mounted. Additionally the technician was unable to diagnose or resolve our issue and instead instructed us to contact our electrician to test the installed CAT6 cabling (and power supply cabling). This cabling has been tested by the electrician on at least two previous occasions as well as replacing the range extender unit. If the technician had called or texted myself while on site I could have confirmed this to be the case. Looks like we will be needing to cover the time/cost of another IT specialist to get this resolved now.