4. A confidentiality policy may not be amended before the expiry of a period of 15 days from the date of publication of a notice of amendment of that policy or, if applicable, before the expiry of a shorter period mentioned in that notice of amendment. The notice must1° indicate the date of its publication;
2° indicate the general purpose of the amendments made to the confidentiality policy, which must be specified in a section dedicated to the policy on the website of the public body;
3° indicate the date of coming into force of the amendments;
4° where the notice mentions a period shorter than the period of 15 days, indicate the reasons for which the policy must be amended in that shorter period.