This is no longer supported. It is just kept for the sake of backward compatibility with legacy library and application. Please look at page 68 of CyAPI.pdf.
I just want to highlight that if you Google "Cypress CyAPI" you will get the (still online):
http://www.cypress.com/file/53106 [OUTDATED: Do not touch...]
The correct(?) one comes with the SDK installation:
C:\Program Files (x86)\Cypress\EZ-USB FX3 SDK\1.3\doc\SuiteUSB\CyAPI.pdf
Do you have an online version where the changelist is also visible?