The Jira Server to Jira Cloud documentation contains the following warning: For a test migration or UAT, we recommend that your test Cloud site is not part of the organization that also hosts your prod site. The prod site should be hosted in a different organization. This is to ensure smooth migration of the relevant users and groups.
If my company name is "XYZ Company," I assume that will also be the name of our production organization. For migration testing, should I set up an organization named "XYZ Company Test" or something like that? If I migrate our user accounts to the test organization and then later migrate the same users to the production organization, would this cause a problem having the same email addresses being linked to two different organizations?