FTTP isn’t rate adaptive ( speed varying with line length/quality ) and there isn’t a training period, there is no settling in, the speed you purchase is the connection speed you get from the outset, if you are not getting what you expect there are a few possibilities, the wrong profile has been applied, your kit isn’t up to it, or the method you are using to test speed is unreliable ( should be wired , not WiFi ) or the router isn’t working as it should…there isn’t a statistic within the router you can look at and ‘see’ what your connection speed is
