Normally the settlement deed specifies a broad class of
beneficiaries and the trustees have a choice of where they can
exercise their powers of appointment.
Occasionally however, the class is reduced to such an extent (often by deaths of the others) that there is only one object/beneficiary. Does that single object/beneficiary have an interest in possession (IIP)?
Re Trafford  1 AER 1108 is considered to have provided an answer of general application
Every case is decided on its own facts. Refer any cases where you consider there may be an interest in possession to your manager.
It follows that if the class is closed, as above, then
A claim to inheritance tax must arise under IHTA84/S65 (1)(a)
when the IIP vests in the last one standing.
If the class is open, the removal of the second-last object makes no difference. It was ‘discretionary’ before, and remains so.