I am intending to switch to BT Infinity shortly, but was slightly disappointed with the speed predictions: around 48 Mbps download and 8 Mbps upload. I am about 250 metres from the cabinet (the BT Wholesale checker helpfully confirms which cabinet I'm served from). I decided to check what sort of speeds some of my neighbours would get, and discovered that houses in the same road, which are maybe 50 or 100 metres further away from the cabinet, are predicted to receive 56 down and 16 up.
Why would the prediction for my flat be so much lower? Do BT predict lower speeds for flats because they assume poor internal wiring or something? The ADSL 2+ speed it predicts is pretty close to what I get, but I note that it predicts lower speeds for same neighbouring houses. Why is their ADSL predicted to be lower speed, but FTTC higher?
The likely speed I can expect is important as it could determine whether I go for Option 1 or 2 (given that the former is now available as an Unlimited option). Any explanations of how the predicted speed is determined would be appreciated.