I'm afraid as my area isn't part of any trial, I have nothing I can give you conclusively. I'm just guessing here but I think at the actual DSLAM it would just be a simple matter of filtering through the G.Fast frequencies ....... ie: just switching them in ??
With remote nodes, they have to fit additional units and provide power and whatever other trickery is involved
As with any trial, there are umpteen different scenario's that can be presented that may affect performance. So, before they 'Go public' with what the EU might expect from G.Fast, I'm guessing they want to trial as many different scenario's as possible ?? I know I would with you lot breathing down my neck
PS ..... love a cider with ice on a really hot day.