The classification by Ofcom leads to a lot of consequences.
One long-running legacy is that Ofcom's classification is meant help an LLU company choose to come and compete. Keeping the old classification is one mechanism used by Ofcom to give a boost to that LLU company
So you should expect classification to remain market A for a good long time yet.
Meanwhile, deployment of fibre, such as FTTC, isn't enough to alter Ofcom's classification of any market A exchange. At last review, they hadn't figured out whether it altered the market.