It will be great to have force PUSH details under PR activity tab. This will help customers understand why the PR was merged in case of PR auto-merge(If a customer force PUSH to a source branch it leads to history rewrite. In case if there was a PR raised from that source branch to master and if Bitbucket detects that there are no changes between the source and master branches after a force push to the source branch, then it will auto-merge the PR considering the change was merged on the force push commit ID).