Hello,
There has been several discussions on the topic (e.g. #344 in French), and here is a brief summary:

Many feeds have date problems: missing, erroneous, a long time in the past, in the future, wrong time zone, etc. Therefore, the date provided by the feeds cannot be trusted, and using it would cause problems such as articles appearing in places not seen by the reader, or remaining at the top of the list all the time, etc.
In order to have a working synchronisation between different FreshRSS sessions (including the cron job updating feeds in the background, and the API for mobile devices), we need to maintain some properties, among others that we should limit the cases when articles are inserted in the database at an older index/date than the newest one. Otherwise, articles may be marked as read even when they are not, and other similar problems. The best approach found was to use the time of insertion in the database as an ID/date for an article.
An improvement on the current system is already planned in SQL: implement defered insertion of new articles (better date sorting) #530 which should solve your precise example.

Let me know if this answers your question, and if #530 is enough to close your issue.

Articles in chronological Order #742

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