Like all the add-ons at the Atlassian Marketplace, Time Between Statuses is set in two ways:
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from the Atlassian Marketplace
1. Write "Time between statuses" in the search box".
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4. Select your site on atlassian.net to install the add-on, then click "Start a free trial".
5. You're all set!
from the Jira Admin page
1. First, click the Apps menu and go to the Find new add-ons page.
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