In Bitbucket Cloud, there is a 4GB or 10GB Repository size limit. To migrate from Bitbucket Data Center to Cloud, you must reduce the size of the repository, but tools like git filter-repo, git filter-branch, and BFG are:

1. Not Supported
2. Do not remove pr refs so the removed objects are not cleaned up on Git GC

The workaround of manually finding all pull requests that reference the deleted files, changing their status from merged to declined, and then deleting them from the GUI is

1. unsupported
2. requires direct manipulation of the Database
3. could be quite dangerous to the overall health of the instance
4. can dereference objects that were not deleted, causing them to be garbage collected as well

Please provide a method within Bitbucket or an Atlassian-approved and supported external tool to perform repository size reduction that handles all aspects of this modification, that can handle bulk repositories, as there could be one or thousands of repositories that need to be shrunk to migrate to the cloud