55 Broadway is to be 'disposed of' according to an article on the TfL intranet. That is crass language for the privatisation of such an iconic LU building; funded by taxes or passenger fares.
This happening as a result of a political choice to end tube subsidies, made by the Tory party as they don't wish to tax their own wealthy class a fair amount. TfL argues it is having to make cuts, usually spun as savings, though it is doing so without much of a fight from senior management or from our Labour Mayor Sadiq Khan.
It is likely that once sold 55 Broadway will be turned into flats for rich people. The same rich people who don't want to pay any tax which is why the building had to be flogged off by LU initially.