Found this strange outcome in the following scenario.

After many years of program exporting the "30000" result (many different version of the runtime) , suddenly at one site, it started exporting the correct "3000" result.

I know how to fix it but why the inconsistent behavior?

       01  PD-RECORD.

              05 PD-DOSAGEX.

                 07 PD-DOSAGE           PIC S9(5)V99 COMP-3 VALUE 30.00.

       01  XTRACT-DETAILS.

           03 XD-SOURCE                 PIC X(8).

           03                                            PIC X.

           03 XD-DAYSSUP                PIC Z(4)9.99.

           03 XD-DAYSSUPV REDEFINES XD-DAYSSUP PIC Z(5)VZZ.

           03                                            PIC X.

           MOVE LOW-VALUES TO XTRACT-DETAILS.

           INITIALIZE XTRACT-DETAILS.

           IF PD-DOSAGEX NOT = SPACES

              MOVE PD-DOSAGE      TO XD-DAYSSUPV

           END-IF

?????? XD-DAYSSUPV = “3000”

?????? XD-DAYSSUP = “30000”

compiler switches  "CCBLFLAGS=-C40re -Dcisiz1 -Z50zlga -Vcxq"