I have an HC-2 (not an HC-2b), running software version 2.06.  I went on line to update my software.  It looked to me like HC software 2.09 is only for the HC-2b, not the HC-2.  Version 2.06 was the highest version available for the HC-2.
Is this the situation?  Or have I confused myself?
Also, just out of curiosity.  What are the improvements of the HC-2b over the HC-2?