It can't be a simple as a date range, because we want to be inclusive for smaller communities.

1. paging is a consideration. 1000 posts per community would allow 10 pages of 20 posts.
2. small communities are defined to be 1000 or less posts, regardless of age
3. large communities would focus on recency, the 1000 post would be recently created or edited
4. Edited can be more tricky, either skip for now or focus on how to limit some kind of mass edit from taking over newly published

Also a good time to be reminded that the published date isn't reliable for a couple reasons:

1. problems in the field have been shown with incoming federation data having future published dates on content. kbin in an easy example, but it isn't limited to kbin.
2. federation can lag due to server overload and problems paths between specific servers, ISP issues, etc. It is rather common to have received a post hours after the published date. Lemmy currently does not track the 'received' date of content.