Any silo that is configured and synchronized will automatically be updated. In the following configuration file App_Config/Include/damforsitecore/DFS.Connect.config there is a hook, which runs by default every 1 minute. The purpose of this background process it to listen for any changes in DAM and synchronize them back to the silo in Sitecore. The timer can be configured to different intervals with which it runs, or completely disables this background process by uncomment the configuration. If you disable this hook, then remember that synchronization is a manual task.