For repos with dependent pull requests enabled, Skara will create a pr/NNNN branch for each active pull request. Whenever the source branch of a pull request is updated in the contributor's personal fork, Skara will push the corresponding pull request branch in the target repo (i.e., the special pull/NNNN/head branch, which is automatically updated) to the pr/NNNN branch. If the source branch is force pushed, but Skara is unable to force push to the pr/NNNN branch, the update will fail with an error message..