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Google's John Mueller responded to a question on Reddit about how to "undo" a 301 permanent redirect. In short, John said you can change the redirect but he does not recommend you set up redirects just to redirect them somewhere else in the short term.
John said, "I'd figure out what you want for the long term, and get there directly." But he added it "happens that people revert (remove or reverse) a redirect, it's not the end of the world." So Google can handle it and it is not the end of the world.
However, he added, "keeping things stable makes everything so much easier though." "In other words, change it if you want, but don't change it again in a week," he said.
So in the best possible case, make sure before you do any permanent redirects, make sure you think it through and don't launch those redirects until you are 100% sure. Sometimes you need to revert things and Google gets that but being consistent is a big deal for Google Search.
Forum discussion at Reddit.
