Thanks, Feridun! I found that link after posting my question and it alleviated some of my concerns, since it seems like Microsoft already has a standard practice set up for moving between tenants. I figured they did, but it was reassuring to see it written down somewhere.
From what I understand, we'll need the existing users set up in the new tenant first and then need to create a map between their account in the current tenant and the new tenant. Then, it's just a matter of making sure the licenses and capacity are available in the new tenant and Microsoft does the rest.
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