Classified National Security Information Protection Act Article 39-1
Information originally approved for permanent classification under this Act shall be re-approved within two years from the date of the amendment and promulgation of Article 12, and the classification period shall be calculated from the date of the original approval. If the re-approval has not been completed within two years, it shall be deemed to be declassified from the expiration date and handled according to Article 31.For information with a classification period exceeding thirty years, if the extension of such period is approved according to the preceding paragraph, the extended period shall be calculated from the day after the original period reaches the thirtieth year, and the extensions shall be approved in accordance with Article 12.