For anyone coming to this in January 2021, GitHub have a new feature to make this really easy. Under settings you can change the name of the primary branch. This preserves all open pull requests. When you make the change, they also give you the couple of commands that you need to run to update your local branch to match.
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For anyone coming to this in January 2021, GitHub have a new feature to make this really easy. Under settings you can change the name of the primary branch. This preserves all open pull requests. When you make the change, they also give you the couple of commands that you need to run to update your local branch to match.