Very strange all round. I too received two recordable boxes (as requested at the time) when I subscribed to BT TV back in July 2016. Indeed the dual offering at that time was the major attraction/selling point because the wife and I have very different TV tastes so separate boxes in separate rooms was / is ideal. The only disappointment at that time was that you could only have one box that could receive 4K and one basic recordable box.
