As the originator of this thread, I thought that to give some closure I'd update for anyone who is interested or to whom it is relevant.
I did look at the link provided above by Darren_B for how to return electrical items to BT, but was somewhat confused by the statement near the bottom of the article saying "We're not responsible for the costs of returning items.". This seemed to be at variance with BT providing postage-prepaid bags. Maybe I didn't read the context properly, or maybe it referred specifically to cases where customers weren't provided with the item by BT as part of BT providing a service, but bought an item, albeit BT-supplied, independently.
Anyway, in the event, when I recently upgraded to Fibre for my broadband, BT sent me a new Hub. Inside the box, among other items was a green postage-prepaid bag for return of old Hubs. There were very clear instructions on the bag, and I followed them "to the letter" this afternoon with my old Hub. Basically you protectively-wrap the old Hub, and its power-cable, put them in the green bag, stick a "barcode label" onto the bag (this is a detachable part of the address label used when they delivered the new kit to you), take it to the Post Office, and get a receipt. When I took my bag into the Post Office, the lady who served me immediately knew what it was for, took the package from me, and gave me a receipt.
There has recently been, in a separate "thread", discussion about recent changes in BT's Terms & Conditions; that probably results in this subject being more important than it previously was.
Mike.
