I sent you the wrong version of my announcement. When you cancel an unmoderated Usenet newsgroup article, your cancel message goes into a special newsgroup and the news software makes sure that nobody sees the cancelled article in the original newsgroup. In the case of moderated newsgroups, the cancel article must be approved, just as the original article was approved, by the moderator. Cancel the article from your news software as you normally would, but keep in mind that the cancel request has to wait for the moderator's attention just as the regular articles do. The moderator will try to take care of cancels first if any arrive, but strongly recommends that articles be proofread carefully before posting.
People are keen on their own sites and often want to post and repost repetitive announcements.
This practice is discouraged. Sites will not be reposted frivolously, and no matter how often you issue updates, nothing will ever be announced more often than once a month. You have posted a new issue of a periodic webzine. Modify all posts which do not conform to the above format, which is the format that most Web browsers can read to provide working links to the announced resource. In other words, the moderator re-publishes the information posted to the newsgroup but does not write it or edit it for content, except for articles posted under the moderator's name.