Sky video is here
https://tv.theiet.org/?videoid=9492 , you can view all the others by clicking the related videos botom right.
The sky guy goes into a lot of detail and interestingly he mentions at the 13 min mark that the ECI dslams have limitations in regards to ipv6 traffic, but hauwei does not. So that it seems is yet another ECI problem. Had to use a nokia session linking feature to overcome it.
Also he mentions approx 80% of sky customers are adsl LLU and approx 20% are VDSL.
The amount of useful information varies from each rep, the BT rep was pretty closed shop as is usual for BT sadly with all their commercial confidentiality.