In the WBC DLM FAQ document we have, it states:
"Does DLM run on all WBC lines?
Yes. The BT Wholesale variant of DLM runs on ADSL 1 and ADSL2+ WBC Lines. FTTX services falls within the Openreach DLM domain."
In the FTTC Handbook (dated January 2011) id doesn't give out DLM specifics at all, but says:
Following installation of service, the line will be allowed to stabilise during the first 10 days after provision and a Fault Threshold Rate (FTR) will be set at 5 Mbit/s downstream for services provided at up to 15 Mbit/s downstream or 15 Mbit/s downstream for services provided at greater than 15 Mbit/s downstream.
Dynamic Line Management (DLM) will be employed to manage line performance to maintain a target balance of speed and stability and is based on amending key variables of a line, specifically: Impulse Noise Protection Capping Interleaving (Please note - there is no order option to remove this). By altering these individual characteristics the line performance is adjusted to meet target stability. The Stability Options offered by BT Wholesale have been mapped to align to the DLM policy options that BT Openreach provide. (Please see below re Maintaining Line Stability)
Line stability is crucial to service quality and to the End User experience and WBC Service provides WBC Customers with more flexibility and more control. WBC Customers can increase or decrease line stability by sacrificing or gaining speed.
WBC Customers and Reseller Customers can choose appropriate line stability profiles that are related to the different needs of End User applications.
WBC Customers and Reseller Customers can change the stability option online as necessary to meet their End Users‟ changing requirements.
Allows a CP to offer a higher line rate, by allowing the line to have a lower stability target than the Stable Option provides.
This setting - aims to keep the line working with only a few errored seconds and retrains each day.
This option allows CPs to offer a higher level of stability by using increased error protection. The line will work at a lower speed than the Stable option and at times it may give rise to increased latency.
Note – Signal to Noise ratio will be set at 6dB for all DLM policies - applies to FTTC only as I know it doesn't do that on WBC.
which are the same as on ADSL I guess although they may work differently.
No mention of Interleaving anywhere although I do know it can be on or off.
So there is no 100% clarification about the initial training. I would take the SIN as being correct as this is what specification the product conforms to.