ST-PI update need functional retest

Hi,

The EWA report, shows the need to update the ST-A/PI "Service Tools for Applications Plug-In" and the Add-On ST-PI (Solution Tools Plug-In).

In the first case, the note is clear about this question, but in the other case it the note  539977 doesn´t say anything about this.

The question is, if we have to retest any Business Functionality to upgrade ST-PI.

Thanks in advance.

Regards.