My exchange (Bannockburn) was fibre enabled a few weeks ago, and the old cab 17
http://goo.gl/maps/Q1EaJ was smaller than this new one, so yeah.... makes perfect sense that they would re-shell cab 17 to give them a bit more space inside for the stuff they need to connect to a fibre cabinet, once they install one. BT are meant to be returning to do some more work between the 10th and 15th of Oct - so hopefully it will be to install a fibre cabinet. I live in the next street... so I'm just hoping this really is the cab I'm on.
I don't think there's a trench been dug there, and covered up again Roberto, I think that's just a mark on the grass where their equipment has been laying or something... could even be a mark where they sat the new cab shell, before they installed it.
The council are pretty active around this area when it comes to cutting grass and triming greenery etc. - so all that was likely down to them.
Thanks for the replies guys!