12.—(1) As soon as practicable after the issue of each batch of postal ballot papers, the CRO shall make up into a packet the corresponding number list of those ballot papers which have been issued and shall seal such a packet.
(2) Until the time referred to in paragraph 20(9) for the opening of covering envelopes, the CRO shall take proper precautions for the security of the marked copy of the postal voters list and the postal proxy voters list.