Updates are pushed manually from the svn into existing branches. Jiaz does this and is not an automated process. We are releasing updates ~once a week at this stage, so you need to wait for the next round of updates to become publicly available. To monitor this you can run jdupdate.jar or monitor the changelog
http://jdownloader.org/changes/index . If Jiaz pushes updates from his home rather than work the changelog doesn't get updated so some times not 100% accurate.