2319699 - How To Set The First Day Of the Time Sheet Period?

Currently the time sheet supports both weekly and monthly time sheet period.

For weekly time sheet period, it is possible to set the first day via configuration explained in the Solution part in this KBA.

For Time Tracking customers, Monthly time sheet period is released with 2H 2405 in restricted release status, and you can require the enablement for it by following the guide as documented in blog post Monthly Time Sheets in SAP SuccessFactors Time Tracking. 
But currently monthly time sheet period follows the calendar month only, so the first day will always be 1st of each calendar month. 
There currently is no way to set up a different monthly period than the calendar month.

• SAP SuccessFactors Employee Central - Time Sheet
• SAP SuccessFactors Time Tracking

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