All petitions submitted pursuant to this part must be filed with the local Bureau official having administrative jurisdiction over the tribe. No petitions will be accepted until a spokesman for the petitioners declares that he/she wishes to make an official filing. Once a declaration of the official filing is made and the petition is given to the local Bureau official, that official shall immediately enter on the petition the date of receipt (this date becomes the date of official filing) and shall inform the spokesman for the petitioners that no additional signatures may be added and that no withdrawal of signatures will be permitted. The local Bureau official shall also acknowledge, in writing, receipt of the petition, indicating the exact number of signatures which are attached and the official filing date. Upon this written acknowledgment of the petition, the local Bureau official shall publicly post at the local Bureau unit serving the tribe a statement of the matter proposed in the petition. This statement shall remain posted for a period of 30 days from the official filing date.