What about the 2011 Postal Services Act? The 2000 Postal Services Act is no longer up to date.
Relevant changes:
In section 105 (application of customs and excise enactments to certain postal packets), after subsection (4) insert—
“(4A) A postal operator may detain a postal packet to which this section
applies until any duties and charges in respect of the packet that are
recoverable by virtue of subsection (3) have been paid.”
37 After section 105 insert—
“105A Section 105: limit on handling charges etc
(1) OFCOM may give a direction to a postal operator—
(a) limiting the amount of any handling charge, and
(b) limiting the length of time for which a postal packet may be
detained under section 105(4A) (and, if a direction is given
under this paragraph, that subsection has effect subject to the
direction).
(2) Where a direction is given to an operator limiting the amount of a
handling charge, section 105(3) to (4A) have effect in relation to the operator (in any case where the charge would otherwise exceed the
amount specified in the direction) as if the charge were equal to the
amount specified in the direction.
(3) Before giving a direction to a postal operator under this section,
OFCOM must—
(a) inform the operator that they propose to give it a direction,
and
(b) allow the operator an opportunity to make representations
about the proposal.
(4) In this section “handling charge” means a charge payable to a postal
operator, in respect of a postal packet, for the performance by the
operator of all or any of the duties mentioned in section 105(2)(c).”
Your move.