XA TRDATA transactions are deleted by the XA backup after they have been posted/prepared.  This essentially deletes any Labor and Shop history specific to the employees.  The Paper-Less history programs save a summary of the labor and shop transactions by shift date and badge number.  They provide a transaction summary that can be used for many different types of reports as well as passing Labor information to a payroll system.  This information is stored after all of the transaction time adjustments, quantity changes, schedule changes, etc… have been made by the select and edit process in XA.    

Please see the attached files for more info about PPLHIST