Strictly, I understand it will be any beneficiary entitled in default of
the exercise of the trustees discretion.
If there is no default beneficiary, the default is to those entitled as
However, the situation you have is not obviously covered by the
Non-Contentious Probate Rules, and so I suggest you might approach the
Probate Registrar to see if they might be willing to exercise their
discretion as to whom to issue a grant.
It may be preferable to have a professional involved as any beneficiary
acting as personal representative/trustee would not be entitled to
exercise any discretion in their own favour.