Back in May I was switched to MaxDSL from my PAYG 2Mb connection.
Other than the generic you will be switched over in the future email notification, I had no idea this was going to happen, until the connection became unstable (unusable). Subsequently I had no idea at first what the problem was. After resetting my WiFi router to its default and than resetting all the security features, it made no difference. As soon as I looked at these forums all became clear. It appeared I was being 'upgraded' to the up to 8Mb MaxDSL.
After scouring the various posts on these message boards, it seemed that it was to be expected to get some disruption for 10 days or so during the switch. I was patient, using a unreliable 128Kb services for 2 weeks, which improved to a stable 512Kb service. Just this week after almost 2 months later it appears that my connection rates have finally become something close to expected. I have run two speed tests over the last two days putting my connection at 3.1 and 2.6Mbs.
Whilst not mind-blowing, as least I can now enjoy some benefit from MaxDSL. My concern is the poor way in which this whole debacle of an upgrade was implemented. My overall judgement is reserved as the connection may prove to be faster and stable, and in time the frustration may fade. But Plusnet have gone down in my estimation and I would no longer recommend them to others, as I often used to.
Many thanks to all the posters who have given advice over the last few months, you were much more useful than the official Plusnet web portal.