Fibre capped at 20Mb

[#1]

The "piece of string" reference is the right one. DLM can relent quickly, just a couple of days, if the improvement is both dramatic and permanent. However, if another dodgy day happens while it is monitoring for stability, it both resets and extends the period that the line must be clear for.
In my last house, DLM intervened twice due to line problems. One recovered after a month, the other took nearly 2 months.
In my previous place (in the days that 40/10 was the top package), DLM intervened on day 3, and never left until BT changed the frequency plan in preparation for 80/20 packages. It then never came back.
@Terranova667:
The "over the top preventiveness" is indeed pretty harsh when considering downloads & web-browsing, which are based on TCP and are therefore self-correcting for errors. However, it isn't too harsh for anything based on UDP, which have no facility for correction or re-transmission; anything streamed will suffer - such as video from their OTT TV service, or Sky's NOW TV. To get the TV service to a broadcast quality, it needs to be harsh.
While I understand the how & why, it doesn't mean I like it though... and would much prefer it to be configurable - and better yet, configurable by the end-user.
However, it seems more likely that they'd introduce vectoring, G.INP and possible SRA before the option to make DLM configurable.

[#2]

WWWombat,
I have had an update from the PN team. They are saying that cross talk is not present on my line. So my line is still banded but no one at PN can offer a reason as to why that might be.
Line info attached below.
Thanks, David

[#3]

Quote from: David

They are saying that cross talk is not present on my line.

I still laugh every time I see that line as part of a test result. Then grimace every time I have to explain that it is relatively meaningless.
The only way to have no crosstalk is for yours to be the only VDSL2 line in the cabinet.
Once there is a second subscriber, you are guaranteed to be sharing some part of:
- The linecard
- The cable from the linecard plug to the cabinet wiring loom
- The tie cable back to the PCP
- If the subscriber then resides in the same direction as you, then you could be sharing some additional cables.
-> there is going to be some crosstalk.
The only way you can have a yes/no result to a "crosstalk test" is to set a threshold, and report whether a line is above or below that threshold; I suspect that the BT test does this, and then sets that threshold high.
As an example, take a look at This article, and check the 2-dimensional heatmap of disturber vs victim.
It wouldn't suprise me for BT to have set their test-failed threshold to be equivalent to a red square, rather than the accumulated shades of blue