The Trust agreement will determine when the beneficiaries have a right to the underlying bank account owned by the Trust. It doesn't matter that B was added as trustee later.
I agree with the previous reply. The beneficiaries' rights to the trust property will be determined by the terms of the trust agreement.
A and B are trustees whose job it is to administer the trust for the benefit of the beneficiaries. As trustees, they have a fiduciary duty to act in the best interests of the trust beneficiaries. Any rights that the beneficiaries have regarding distributions from the trust exist regardless of who the trustees are and when they became trustees.
But the trust terms will spell out how and when distributions can be made to the beneficiaries, including how and when the trust should terminate and any remaining principle distributed outright to the beneficiaries.
For example, if both A and B trustees were to die in a common accident, the trust terms should identify who is next in line as successor trustee. If the trust terms are silent, then that determination would have to be made by a judge. But the death of both A and B would not mean that the trust would terminate and any assets distributed to the beneficiaries -- unless the terms of the trust provide for such an outcome.
Hope this helps.
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