If you are using the Blogs platform for news you may want to sometimes add an entry which stays on top for a while. One way to do that is to change the Publish Date field to a particular late date (e.g. sometime in 2020 or the time when the information in the announcement “expires”). It will stay on the top because it’s the most “recent” entry.
And no the system will not choke because the date hasn’t actually happened yet. Best of all, you can adjust dates to reorder items. Just use this power only for good.