If you are upgrading to Oracle Database 12c for an Oracle Utilities Application Framework based product then you can use Oracle Enterprise Manager to manage your Information Lifecycle Management based data management solution.
To use it you simply install Oracle Enterprise Manager and then register the 12c database instance (PDB and non-PDB are supported) and then when selecting the database target use the Information Lifecycle Management menu option from the Administration --> Storage menus. For example:
This means that you can use Oracle Enterprise Manager as a viable alternative to ILM Assistant for Oracle Database 12c targets.