Most dates and times in the installed base are relative to the end user’s time zone, both when Installed Base Item Maintenance (11.3.1) creates ISB records directly and when you create them as part of another service activity such as RMAs or calls. Install Date, Warranty Expiration Date, Last PM Date, and Next PM Date are among the fields affected.

The exception is any date set by programs outside the Service/Support module, such as Invoice Post. Since these programs are outside the scope of SSM, they update ISB records with the system date and time.

The install date is important in determining valid warranty coverage. If end users are far enough away that time zone differences create date differences, you can manually update the install date created by Invoice Post.

Sales order routines also set the Ship Date value displayed in Installed Base Item Maintenance. This date reflects the domain time zone.

See here for details about this function.