Change Author is an option provided to Administrators to change the author of an article in your Knowledge Base from one person to another.
To change the author of an article, click open the article > Edit (on the right pane) > Edit article properties > select the desired Author > Publish

Whenever a customer provides feedback for an article upon downvoting, a ticket would be created on your end and the author will automatically be marked on the ticket as a Watcher

This can be helpful in scenarios like these:

When articles are written by someone who is no longer with your company

Example - Jim has been hired as a content writer by Saul's Emporium. One of his responsibilities is to ensure that all solution articles are up to date. While at this task, he notices that many solution articles were written by Sally who is no longer with the company. He then reaches out to the Administrator to get his name changed as an author so that he may receive notifications whenever someone provides feedback on those articles. 

Note: If the author is not changed to Jim or anyone else, Sally will remain the author of this article even though she has left the company. 

When articles are written by someone who has moved on to another department within your organization 

Example - Jim moves from the content team to the public relations team at Saul's Emporium and Michael is hired to replace Jim. The Administrator then changes the author from Jim to Michael. Michael will now receive notifications if someone provides feedback on the articles originally written by Jim.

When the content writing responsibility is shared by multiple people on a team

Example - Michael is finding it difficult to manage all the content by himself. Dave and Fiona have been hired to share Michael's current workload. Dave is now responsible for all solution articles under the furniture section of Saul's Emporium. The Administrator then changes the author from Michael to Dave so that Dave will be able to receive notifications.

In all of these scenarios, the Change Author option also makes it easier to people within an organization to reach out to the author of an article if specific content edits are to be made.

When the agent is deleted

If the author of an article is a deleted agent, the author will be displayed as Deleted agent. You can always change the author name to a different agent to receive notifications on article feedbacks.