MaxSem wrote a small shell script triggered by a cron and maintained in puppet https://gerrit.wikimedia.org/r/#/c/68309/
Given a list of wikis / articles, the script will each day copy them to a beta wiki.
The point of that bug is to migrate that under Jenkins, that will let us tweak the job easily without relying on ops to merge our change and will also let us trigger the sync manually by rerunning the job.
See also