I am around 450 to 500m from my cabinet and the modem gives a figure of 63Mbps ...
So, moving a little further way suggests that the BT estimate could be about right - but it will depend on noise, including cross talk, cable quality, joints cable size &c. You may also find that it syncs quite high to start but gradually drops back a little and that will be as others are installed and the crosstalk noise increase.
If you get 60Mbps - I will be very surprised and even 55Mbps will be a good result.
M H C
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