On Wed, 27 Jun 2012 07:51:03 +0100, Caecilius
wrote:

Can I install a BT master socket and just leave it to BT to connect
the A/B pair, or are only BT allowed to do that?

In new builds BT may use an external NTE5 (XNTE) usually positioned
outside near the front door. However, despite only recently being
introduced the XNTE is now being discontinued once stocks are
exhausted as it doesn't support vDSL.