I was unable to find any documentation on this as well, but I have requested it here:
As you have figured out, System Users are users required either by add-ons or used by Atlassian Staff to troubleshoot your instance. They do not take up a license seat.
I hope this helps! Let us know if you have any additional questions.
Hello, Community! My name is Gosia and I'm a Product Manager on Jira Server and Data Center here at Atlassian. Since 2002 when we launched our public issue tracker, jira.atlass...
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