if I got you right you opened https://www.atlassian.com/software/jira/service-management/update and got an error 404 in your browser.
When I tried it some seconds ago the page is redirecting me to a download page.
Could you please confirm it is working for you now?
In case you were looking for some other information please do let us know.
A more general information on upgrades is to be found here:
We often have questions from folks using Jira Service Management about the benefits to using Premium. Check out this video to learn how you can unlock even more value in our Premium plan. &nb...
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