Your comments

any update? any intention to fix this? if you intended to kill instablog readership you've succeeded.

As of a few weeks ago you used to be able to subscribe to any author's blog posts using a URL like this:
https://seekingalpha.com/author/paulo-santos/instablog.xml

However, they appear to all have stopped working. Was this intentional? How do you subscribe to an author's blog posts in a feed reader now?

I did check and the https://seekingalpha.com/author/paulo-santos.xml URL only contains articles not blog posts.