This section applies to a person who is given a notice under section 8 or 8A.
Before the end of the withdrawal period, HMRC may withdraw the notice (whether at the request of the person or otherwise).
But the notice may not be withdrawn if—
the person has made a return under section 8 or 8A in pursuance of the notice under that section, or
the person has been served with notice of a determination under section 28C by virtue of the notice under section 8 or 8A having been given to the person.
If ... HMRC decide to withdraw the notice under section 8 or 8A they must do so by giving the person a notice under this section.
A notice under this section must specify the date on which the notice under section 8 or 8A is withdrawn.
For the purposes of subsection (2) "the withdrawal period" means—
the period of 2 years beginning with the end of the year of assessment to which the notice under section 8 or 8A relates, or
in exceptional circumstances, such extended period as HMRC may determine.
Withdrawal of a notice given to a person under section 8 or 8A in relation to a year of assessment does not prevent HMRC from giving the person a further notice under that section in relation to that year.