We have a Bitbucket Data Center instance with several mirrors created in different sites.

The mirrors are available in the Bitbucket web interface, and can be selected to get the cloning URLs:

However, when setting up a job in Jenkins using the Atlassian Bitbucket Server Integration plugin, only the primary server is seen:

 

The issue is seen on all mirrored project, and impacts all mirrors.

BitBucket server: 8.19.0

Bitbucket Server Integration: 4.0.0

Jenkins: 2.463