r2b2:... when it comes to changes like this, I'm assuming W87A, W87B, W87C, etc. all wrap up into the main node that is being upgraded to - i.e. they are more just sub-distribution node type things?
I'm not a network engineer and could well be wrong but from what I've picked up from emails etc I understand they've been busy upgrading the core network then complete testing and are now cutting over nodes individually. I assume it could easily vary in individual areas depending on the local requirements.