Very interesting! Any possible hint to a solution is highly appreciated on my side!
Meanwhile I found this addon -
https://vborg.vbsupport.ru/showthrea...35#post1887735
It changes some code-portions and is able to post rss-feeds into posts, even into only one post, if wanted. That reduces the tons of newpost-entries to just one. The tool is capable of preserving the dateline and as far as I catch this, this would mean, that the initial post-creating-time is kept. So every new rss-feed-entry wouldn?t touch the newpost-search anyway.