For the purposes of this section the qualifying condition is that the National Crime Agency has reasonable grounds to suspect that—
If the qualifying condition is satisfied the National Crime Agency may serve on the Commissioners of Inland Revenue (the Board) a notice which—
Service of a notice under subsection (2) vests in the National Crime Agency, in relation to the person or the company (as the case may be) and in respect of the period, such of the general Revenue functions as are specified in the notice; but this is subject to section 318.
the National Crime Agency—
A notice under subsection (2) and a notice of withdrawal under subsection (4) may be in respect of one or more periods.
Service of a notice under subsection (4) divests the National Crime Agency of the functions concerned in relation to the person or the company (as the case may be) and in respect of the period or periods specified in the notice.
The vesting of a function in the National Crime Agency under this section does not divest the Board or an officer of the Board of the function.
If—
the authorisation is not required in relation to the function as so vested.
It is immaterial whether a chargeable period or any part of it falls before or after the passing of this Act.