I'm guessing this is an ugly and tricky task to complete in entirety with straight forward migration tools at hand. My guess is you are going to have to get dirty and export the data to JSON & CSV, and try and import with that.
From what I'm reading, it doesn't sound pretty. Have a look at this thread.
Hello everyone, I am a product manager in the Jira Cloud team focused on making sure our customers have a delightful experience using our products. Towards that goal, one of the areas which is extr...
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