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.
I'm Alison Huselid, Head of Product for Data Center at Atlassian. As we shared in our last post, we’ve been working on a solution for those of you who work for charitable non-profit organizations tha...
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