There is talk about a trial of 18/2 FTTC speed variant, the trial was aimed at customers currently getting less than 2Mb speeds, there were 2 million getting less than 3Mb, and 900,000 of those already have FTTC available. From the ISP forum slides, BTWholesale decided not to take part in the trial. I think there were other restrictions, like it was only for upgrading packages while staying with the same ISP. Perhaps it was even aimed at getting ISPs to move customers from ADSLx to FTTC 18/2, while the ISP keeps their customer paying the same as whatever they're currently paying. Essentially they'd be paying ADSL2+ prices for ADSL2+ speeds, it just happens to be delivered via FTTC.
Edit: the 2 million and 900,000 figures were for those getting less than 3Mb speeds, in September 2015, but the trial was later aimed at those receiving less than 2Mb speeds.