I am not sure I understand what you mean? There is no need to "make room" for new posts. New posts always go on top as the old one just keep moving to the back of the list. The messages you see saying that a post has been moved just mean that it has been moved to a section where the subject was more appropriate. For example, somone posts a video in the announcements section, we may move that to the mulitmedia section. We don't delete old posts unless they contain objectionable material but that does not stop us from continuing to create new posts.