Her Majesty may by Order in Council amend this Part so as to—
specify, as an additional devolved tax, a tax of any description, or
make any other modifications of the provisions relating to devolved taxes which She considers necessary or expedient.
An Order in Council under this section may also make such modifications of—
any enactment or prerogative instrument (including any enactment comprised in or made under this Act), or
any other instrument or document,
as Her Majesty considers necessary or expedient in connection with other provision made by the Order.