Helen, you are on the Town Council, and you don't know? This is typical of the shady, furtive manner in which the Charities conduct their business.
The Town Council is supposed to nominate five out of fifteen of the Trustees. It does not have to be Councillors. The criterion for normal members (nine of the other ten) is "persons who through residence, occupation or employment, or otherwise have special knowledge of the Parish of Bourne". The other trustee is the Vicar, ex officio. The council has never sought out a non-Councillor to become a nominated Trustee.
It stands to reason that, out of courtesy, let alone under the obligations of legislation, these Councillors amongst them ought to report back to the full Council after every meeting of the Board of Trustees of the United Charities. Therefore, the Council ought to be fully informed about the plans the Charities have for the Red Hall. The Council ought to have the power to mandate their five members to support their collective view to the Trustees. However, the five Councillors persistently refuse to report back - they are content to keep their colleagues whistling in the dark.
Every so often, the Trustees come up with schemes. Occasionally they are sensible, but usually they are ill thought-out and contentious. They never consult with the townspeople, who are the beneficiaries of the original legacies. The trustees collectively are gifted with very little imagination (apart from how to hold on to their hoard of treasure), that is why they are trustees. Instead of asking people what they think, and seeking help to find the best possible solution to problems, they moulder in their own Stygian gloom and seek to do as little progressive as possible.
It is unlikely to change, unless a challenge is lodged with the Charities Commission. That would be an expensive business with no reward, other than serving fellow men (and women).