If I call `/repositories/{workspace}/{repo_slug}/pullrequests/activity`, as documented at List a pull request activity log, I do get a list of pull request updates in that repository, but the `changes` field in the `update` object doesn't reflect the actual changes in the pull request at hand.
For instance, if a new PR is created, the `update` object makes it appear as if an earlier PR was changed, step by step, into the new PR. The `changes` object will contain a title update, where the `old` field is the title of an earlier PR, and a `reviewers` field will contain a list of removed reviewers, followed by another update where reviewers are added.
This almost looks like a database cursor pointing off by one.
