Plusnet... why are throttling my line using your out-of-date IP profile cache???

[#1]

We all know BT stores and manages the "IP profile" every ADSL-enabled line.  BT caps my bandwidth to whatever my IP profile is currently set to. So Plusnet will never see my speed exceed the IP profile, because BT has capped my connection before any Plusnet equipment gets involved.
When BT changes my IP profile, their systems instantly see the change and my bandwidth cap changes.  All great.
But Plusnet is caching BT's IP profile value for all their customers in a Plusnet database.  Plusnet uses this cached IP profile to cap my speed.  As BT has already capped my speed, it's bizarre and pointless that Plusnet is applying a bandwidth cap - it's already been done by BT.
The BT speedtester shows my IP profile in the *BT* system after a successful speed test.  The Plusnet "High Speed Broadband" page shows the value cached in Plusnet's system.  You might want to compare the 2 values and see if Plusnet are artifically slowing your throughput speed.
So if I hold a higher sync rate connection that pushes me into a higher IP profile band for at least 3 days, BT will increase my IP profile and I will see faster throughput.
But, sadly I don't, because the Plusnet cache seems to either take a day+ to update with BT's change, or it just doesn't update at all.  I'm then left with a line that BT is capping at, say, 4.5Mbps and Plusnet is helpfully capping at 4Mbps, the out-of-date IP profile that Plusnet has cached.  So BT thinks my line is running faster, but I see no improvement until I either wait an undetermined amount of time for the Plusnet cache to update (which it often doesn't), or call Plusnet Support and ask them to manually update their stale value for my line.
I can understand why an ISP might need the ability to limit my throughput to a low value (e.g. I don't pay my bill; I exceed a monthly usage limit etc), but I imagine for most customers, most of the time, the only throughput capping should be done by BT.
I've been given a number of reasons why Plusnet needs a cache of my IP profile.  For "traffic management" is the most often given reason.  But this doesn't make any sense... BT has capped my line already.  It makes no sense that Plusnet caps my line - BT does that, so Plusnet doesn't need to.  Given that Plusnet can cap me using an INCORRECT IP profile that doesn't get updated is just damn unfair.
It takes enough time to get an IP profile increase.  Seriously guys, you're not helping - you are causing delays, frustration and wasting Plusnet Support time and resources when they need to manually update your cache.
I urge all Plusnet customers to check your cached IP profile via the Member's Centre.  If it's lower than the IP profile BT says your line is running at on the BT Speedtester results page, let Plusnet know.
As for Plusnet, please will you stop this madness!

[#2]

We match the IP profile against BT Wholesale so we can apply per user QoS to your line. This allows us to prioritise your high priority traffic above low priority traffic. If we didn't have this profile then we wouldn't know the maximum rate your line could support, therefore if we allowed more traffic through on our side of the network than your line could support you would see random packet loss at the BTW BRAS and this could be any type of traffic (VoIP, P2P etc).
So by applying the profile on our side we can control what traffic is affected first, therefore allowing high priority traffic to be unaffected and only the lowest priority traffic to be affected.

[#3]

Thanks for the info.
But why does your system often not know about an IP profile increase on BT's system?
jim:quote

[#4]

See this existing thread - except there hasn't been an answer
http://community.plus.net/forum/index.php/topic,105726.0.html

[#5]

This has been going on and on for ever.
Plusnet systems are not picking up the data from the BT systems
As to why...........
I'm sure I saw a post where PN said they knew something about why it not happening - but the fix is not a simple one.
I've found the Plusnet IP is always just lower than the BT one regardless - it's seems to be rounded down to the next 0.1Mbps down.
Even if/when its working its meant to take 12 hours or so to update.
I've no idea if this is to avoid temporary glitches in the line producing low syncs which then are ignored if they are shorter than 12 hours as by then the sync and BT ip rate will have returned to normal.
Or whether is just that its all delayed by 12 hours and follows the BT IP setting exactly.

[#6]

How are you checking your cached IP profile via the Member's Centre?
I looked but was unable to find my cached  IP profile.

[#7]

https://portal.plus.net/my.html?action=stable_rate - current line speed