When using the Atlassian Bitbucket Jenkins plugin with multibranch pipelines, merging a pull request causes the corresponding PR branch to be automatically disabled by the orphaned item strategy, regardless of whether the source branch is deleted.

Current Behavior:

• After a PR is merged, the PR branch is disabled in Jenkins multibranch pipeline jobs, even if the source branch still exists.

Desired Behavior:

• The PR branch should only be disabled if the source branch was actually deleted after the merge.

Steps to Reproduce:

1. Create a PR in Bitbucket and ensure a Jenkins multibranch pipeline is triggered.
2. Check Bitbucket Webhook Trigger, All Pushes and Pull Request Opened or source branch updated
3. Merge the PR, but do not delete the source branch.
4. Observe that the PR branch is disabled in Jenkins, even though the source branch still exists.

Impact:
This causes confusion and disrupts workflows where source branches are intentionally kept after merging PRs.