I cannot enter (other) changes in separate holiday allowances and/or 13th month wage runs, is that correct?
Yes, that is correct. You can only enter changes in periodic payroll processing and additional payroll runs. In the course of the year, it is possible to enter advance payments for employees that will have to be deducted from the payments for vacation allowance and/or a 13th month. Advance payments on vacation allowance have to be entered under wage code 851 and advance 13th month payments have to be entered under wage code 852.