This is a simple job that publish any site with this site property:
where the date is today's date in the moment the job runs, and is in that format (yyyy/MM/dd).
And it unpublish sites following the same criteria about site properties:
If publish and unpublish date is the same, it unpublish it.
If someone find this useful I can try to do a pull request to add this to Sakai 11. Meanwhile here is the patch in the case someone wants to use it.