I'm trying to find contact details of someone in Openreach that might know details about what exactly is being upgraded in the exchange, and it's proving tricky.
My understanding is that Openreach are responsible for the FTTC cabinets and fibre install, and equipment/fibre termination in the exchange up to and including the Layer 2 Switch that then transfers the data to BT Core network via 21CN. BT Wholesale are responsible for provisioning the 21CN backhaul in the exchange; receiving data from the Layer2 switch and transporting it back to BT Core and beyond.
I presume therefore that is an Openreach job to provision any possible new MSAN in the exchange for ADSL2+ if this is on the cards.
The only contact I can find is for Openreach new installations headquarters in Edinburgh. An email to them last week has gone unanswered so far.