@Marvin: Is it possible to override the pull > prefect.deployments.steps.git_clone > branch value for a single flow run, so I can test a change made on a dev branch, without having to redeploy the flow only to redeploy it again later to restore the original branch value?

fixing marvin now, but short answer, yes, but it could be easier

pull:
  - prefect.deployments.steps.git_clone:
      repository: <https://github.com/org/repo.git>
      branch: "{{ $CLONE_BRANCH }}"

prefect deployment run my-flow/my-deployment \
  --job-variable 'env={"CLONE_BRANCH": "my-feature-branch"}'

Thanks @Nate. Funnily enough, independently of your answer, this is the route I ended up taking

nice!