Phame blog posts have entries in their blogs’ feeds that have an
updated date, but no
published date. This means that whenever they’re updated, they are pushed to the top of the feed by (chronological) feed readers. (The entries aren’t actually reordered in the Atom source, it looks like.)
An updated blog post shouldn’t be treated as being new, or at least it should give the consuming feed reader the option as to which timestamp is used (by including both).
Not sure; this one: https://phabricator.wikimedia.org/
Create a blog post, wait a bit, edit it, look at the feed.
I also reported this here: https://phabricator.wikimedia.org/T188890 because that’s where I’ve observed this problem.