Are you on ADSL (up to 8 Mbps) or VDSL (Up to 38 or 76 Mbps)?
What that sales droid said might be half correct, you could get a considerable speed increase by switching from ADSL to VDSL. The village has recently become "fibre enabled", people down there were lucky to get 1 Mbps on ADSL. VDSL from the new cabinet just outside the village provides those same people with 30 to 40 Mbps. However the fibre only runs to the cabinet (in the same ducting as the phone lines from the exchange), but the last hop from the cabinet to premesis is on the existing copper.
If he insists that the fibre runs all the way to the premises and only wants a £100 or so install fee make it a term of the contract, record the phone call, get emails, anything. Then don't be disappointed when they don't deliver/cancel the order or be prepared for a BIG argument if they do.
Fibre To The Premises (FTTP) is available but install costs have four or five figures before the decimal point. BT are also playing with FTTP on Demand but last time I looked they hadn't really thought about costings. FTTPoD ought to be vastly cheaper as any "excess construction" is only charged from the nearest fibre node (joint box in the installed fibre network) which may well be very close rather than a "point of precense" that could be tens of miles away. But for anything over 200 m from the fibre node you are still looking at four figures...
BT Openreach now have huge amounts of spare capacity to all but the smallest places. The afforementioned village cabinet serves about 100 customers and required 40 km of new fibre to be installed, admitedly that 40 km of fibre also serves another half dozen or so cabinets in this exchange area (and possibly enroute as well) but there are only
1200 customers in this area total, of which a number are too far from a cabinet to benefit from FTTC.Once the dust has settled from BDUK Phase 1 and proper work starts on Phase 2, BT Openreach will be looking at how to get this spare capacity earning money.