The SNR target for my connection appears to have been reduced to 3dB, without me making any sort of request for a reduction. This has given me a sync rate of 3008 kbps, the fastest I have ever seen. Naturally I'm not complaining, but is a 3dB margin sustainable or will my connection become less reliable? Or is it simply the case that with increased take up of fibre connections, those remaining on ADSL2 have less noisy lines?
If the DLM sees the line is very stable with few errors for an extended period it will reduce the target SNR margin. Keep an eye on the detailed router stats, not only for disconnects but also at the error rates.