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This will be a significant upgrade that includes several major changes to the way Jira both looks and works. We are currently running v3.15 of Jira, meaning the new version will include features and fixes offered by all interim versions (4.0 & 4.1). Listed below are links to the release notes of all these versions. We would encourage you to read through these as they provide highlights details of all the major things that will be changing once we upgrade.
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