Auto-Tier LUNs on Flash System may not be automatically released

If you have an Oracle Engineered System like Exadata or Exalogic, you may want to know how in some cases the Flash System doesn't get space released as found in MOS document "FS System: Deleting Auto-Tier LUNs May Not Increase Free Space for a Storage Domain" via article ID 2015849.1 so you can take a proactive look at your system to see if you suffer from this as well.