Substitution Variable condition not working within IF condition

Summary:

Issue while passing Subs variable inside IF condition.

Content (required):

Hello All,

Here we are performing forecast calculation by passing subs variable inside IF condition where its not producing correct results.

We are performing currFcst as Q2Fcst in below script example, expecting condition to go inside Q2Fcst ELSEIF condition , display 4, whereas it goes only within Q1Fcst IF condition with &currFcst Variable points to Q2_Fcst in application

Hope i'm not doing anything wrong here, please share your thoughts on below issue

FIX (@RELATIVE("921100",0), "OEP_Forecast", "OEP_Working", &FcstMnth : Dec) 

      "Calculated" (

        @CALCMODE(BOTTOMUP);

        #Missing;

        IF (&CurrFcst == Q1_Fcst)