You should have no problem upgrading from v7.1.2 to v7.4.2. Just make sure you back everything up and follow the standard upgrade process. If you were on a v7.0.x version you would have some issues.
From the link below:
Version specific detail
This approach requires you to have the JIRA administrative rights. The main aim of this article is to help you achieve an organized, easy-to-maintain workflows in your JIRA instance thereby, reducin...
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