Here's my experience. The target SNR is 3.0dB. In the busy times it drops to as low as 2.5dB, but in quiet times rises to 3.6 dB. If I reboot at 3.6dB it resets at 3.0 / 3.1dB and the sync increases. However, if the busy time is very busy the SNR drops to below 2.5dB and might trigger a disconnection. Then it resets to 3.0 / 3.1dB but at a lower sync (more stable). Then in the quiet times it pops back up to 3.6 or more.
I did mention to the Plusnet handler that it was a bad time to switch to ADSL2+ and train the line (Jubilee, Euro 2012, Olympics). I got a really decent sync on Friday morning, only to get a disconnection when the country decided to go online around the time of the England match. No idea why, since it's on FTV telly, but those are the trends I'm seeing.
Edited by camieabz (Sun 17-Jun-12 13:23:42)