I'd previously redirected (from A to B), and wanted to change back (from B to A). I found it worked this way: On A, cancel the redirect to B On B, delete the old alias of A On A, set up an alias of B On B, set up the redirect to A The one issue I saw is that B started moving my followers, and a Rate Limit error showed up on A for a few minutes. After a short period it stopped complaining, and seems to have done it okay.
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