Effective Date for Time Evaluation without overwriting HRS

Hi SAP expert.

I am new to HR Schemas though I am familiar with Z8+ and IBM ALC, and this chip don't seem to have any registers.🤪

I created a variable ZDESC in V_T511K and am setting the value to 0 before the effective date and 1 after the effective date.

I created a PE02-> type T (time evaluation) Rule named ZDSC which returns T after the effective date, F otherwise.

* **** HRS=CZDESC

* **** HRS?0

* **** * SCOND = T IF

* **** = SCOND=F IF

I updated my PE01 time keeping schema &W30 to call the rule as follows:

"

" complex stuff before

"

IF ZDSC

"

" new time keeping logic

"

ELSE

"

" old time keeping logic

"

ENDIF

"

" complex stuff after

"

Now my concern is that I am now overwriting HRS by setting it to ZDESC. I do not wish to overwrite HRS. Is there a way to do the following, or is there a better way to accomplish this? I do not wish to have to determine whether or not HRS is in use by something else.

* **** TEMP=HRS " Imagined code

* **** HRS=CZDESC

* **** HRS?0

* **** * SCOND = T IF

* **** = SCOND=F IF

* **** HRS=TEMP "Imagined code

Thanks,

Martin