ISPs offering FTTP

In anticipation of having FTTP available at some future date (engineers in the road with Fibre installation equipment), I have been looking at available ISPs. Although it appears to be a limited offering from the major players, I notice that of those that do offer the service, most of them say line rental included. Does 'line' refer to the Fibre cable or the existing copper cable? From my point of view I would ditch the copper and go down the VOIP route. Would it therefore be possible to decline the line if that refers to copper and just take the Fibre service?

People like Zen Internet do phone and FTTP packages and also data only, others vary.

BT is always with phone be that over copper (most common if existing copper at premises - there are exceptions) or over fibre for new build homes which have no copper.

Declining the line means a different wholesale product pricing and there is generally not a massive saving between the two.