For time sheets, just generate new time periods with the new starting day, as per the TM config guide.
Staffing profiles, budgets, benefits, etc all use different (fiscal) periods generated during installation which are not able to be modified. The following is what I rec'd from CSO on this issue:
Running the Script to Generate Periods Note: If you need to change the start day of the week from its default (Sunday) for a new installation of PPM Center, you must change it before generating any periods and you must retain the new setting thereafter. See Changing the Start Day of Weeks on page 14.
Changing the Start Day of Weeks Note: If you need to change the start day of the week from its default (Sunday) for a new installation of PPM Center, you must change it before generating any periods and you must retain the new setting thereafter.
Generating Periods for Retail Calendars Note: HP strongly recommends that you establish periods for retail calendars only on new installations of PPM Center, that is, installations that have not been upgraded from previous versions or used for production. If you change the start and end dates of months for which existing financial data used non-retail calendars, the data becomes inaccurate and meaningless, because it has been tracked using Gregorian calendar months.
The START_DAY_OF_WEEK in "periods.conf" (in PPM_HOME/conf/fiscal) can not be modified once it is set at Install time.
When PPM is installed, it defaults to the following:
Periods are generated in the install process, so once the install is completed, the PPM instance will be set at the above.
If you are performing a fresh install, the "periods.conf" file can be changed in the Install package (ppm-910-install.zip) before the install, then re-run the install again. This will generate correct fiscal periods.
Therefore, it is NOT recommended to modify the Fiscal periods after being set, in order to prevent data loss.