For more information about updating distribution points with source file content, see How to Manage Distribution Points in Deployment Packages.
A manual software update deployment is the process of selecting software updates from the Configuration Manager console and manually initiating the deployment process.
Or, you can add selected software updates to an update group, and then manually deploy the update group.
Talking about software updates, in SCCM 2012 R2 there are few new features added which includes a new maintenance window dedicated for software updates installation.
This lets you configure a general maintenance window and a different maintenance window for software updates.
You can redistribute a package to copy the content files in the package to distribution points or distribution point groups, overwriting the existing files.