I have a Bitbucket “Mirror Hook” (found in the “hooks” section of settings). It was correctly mirroring everything from Repo A into Repo C. But now, we have to migrate Repo A to a new location, Repo B. So I move everything over to Repo B, disable all the Hooks and Webhooks in Repo A, and then set up an identical Mirror Hook from Repo B to repo C. The Web Hook requires a ‘username’ and ‘password’, and the password is generated via Http Access Token option in the Bitbucket settings.