Var
  iList, tmpPos: Integer;
  tmpList: TStringList;
  tmpSubDir, tmpStripped: String;
  tmpDate: TDateTime;
Const
  ctDateFormat = 'yymmdd';
  ctOlderThanDays = 500;
Begin
  psExitCode:= 0;
  psVSA := '';
  // ... add your code here
  psLogWriteStr('Checking Subdirs of Source: ' + psSourcePath);
  tmpList := TStringList.Create;
  Try
    Try
    psListPaths(psSourcePath, '*.*', 1, tmpList);
      // Iterate
      For iList := 0 To (tmpList.Count-1) Do
      Begin
        tmpSubDir := tmpList.Strings[iList];
        psLogWriteStr('Source SubDir: ' + tmpSubDir);         
        tmpStripped := psStringReplace(tmpSubDir, psSourcePath, '');
        psLogWriteStr('Source SubDir Stripped 1: ' + tmpStripped);
        tmpPos := Pos('_', tmpStripped);
        If tmpPos > 0 Then
        Begin
          Delete(tmpStripped, 1, tmpPos);
          psLogWriteStr('Source SubDir Stripped 2: ' + tmpStripped);
          If length(tmpStripped) >= Length(ctDateFormat) Then
          begin 
            tmpStripped := Copy(tmpStripped, 1, Length(ctDateFormat));
            psLogWriteStr('Source SubDir Stripped 3: ' + tmpStripped);
            If StrToIntDef(tmpStripped, -1) > 0 Then
            Begin
              tmpDate := psStrToDate(tmpStripped, ctDateFormat, #0);
              psLogWriteStr('Source SubDir as Date: ' + FormatDateTime(ctDateFormat, tmpDate));
              // Check Older Than
              If psIncDay(tmpDate, ctOlderThanDays) < Now Then
              Begin
                psLogWriteStr('Source SubDir older than valid for ' + tmpSubDir);
                psVSA := psVSA + tmpSubDir + '*;';
              End;
            End
            Else
              psLogWriteStr('Source SubDir: ' + tmpSubDir + ', date part not a valid number');
          End
          Else
            psLogWriteStr('Source SubDir: ' + tmpSubDir + ', date part not long enough');
        End
        Else
          psLogWriteStr('Source SubDir: ' + tmpSubDir + ', date part not valid');
      End;
      // Check psVSA
      If Trim(psVSA) <> '' Then
      Begin
        psLogWriteStr('psVSA will be used as Directory filter: ' + psVSA);
        psExitCode:= 1;
      End;
    Except
      psLogWriteStr('Checking Subdirs of Source "' + psSourcePath + '" Exception, Exit');
    End;
  Finally
    tmpList.Free;
  End;   
End.