In reply to a post by iand:

want to know how to get rid of the old router as have no need for it now. Do SKY support athe wee initiative? will look at their web site.

They should take it back, I think there is a return address, might be a label in the box your new one came with.
(WEEE is a legal requirement for businesses!).

In reply to a post by Kr1s69:

2nd option - sky can do firmware upgrades automatically - why couldn't my firmware be updated remotely to support fibre?

Apparently the only way to get the fibre firmware on a v6 2504N is using the firmware recovery option, it doesn't work using the normal update route, and even then it's a bit hit or miss whether it works. Someone on one of the Sky forums tried it a while back.