When a user validates payroll for a given Payroll Accounting Area, no changes are permitted to Master Data, so no Absences can be added when payroll is validated (locked).
When using CATS to enter time, Attendances and Absences can be entered when payroll is validated but the entries are not taken into account unless payroll is put into "Correction" mode and program RCATSTAL is executed to transfer these entries from CATS to IT2001 and IT2002.
I've never worked with ESS, but you should look if there is a similar process. If so, the program the Manager uses could generate data in a Batch Input File and the Payroll Supervisor could then execute (through sm35) when Payroll is put into "Correction".