question

I need to covert YYYYMM string ( [DimDate].[Calculation Period].[Calculation Period]) to date in MDX when importing data from Analysis Service OLAP database to Power Query (to keep the Native Query active and apply incremental refresh)
Here the native query

 SELECT
     {
         [Measures].[Quantity],
         [Measures].[Sales YTD],
         [Measures].[Sales]
     }ON 0,
     ORDER(
         NONEMPTY(
             CROSSJOIN(
                 CROSSJOIN(
                     CROSSJOIN(
                         CROSSJOIN(
                             CROSSJOIN(
                                 CROSSJOIN(
                                     CROSSJOIN(
                                         CROSSJOIN(
                                             CROSSJOIN(
                                                 CROSSJOIN(
                                                     CROSSJOIN(
                                                         CROSSJOIN(
                                                             [DimDate].[Calculation Period].[Calculation Period].ALLMEMBERS,
                                                             ADDCALCULATEDMEMBERS(
                                                                 DESCENDANTS(
                                                                     [DimDate].[Date Hierarchy].[Year].ALLMEMBERS,
                                                                     [DimDate].[Date Hierarchy].[Month Desc],
                                                                     LEAVES
                                                                 )
                                                             )
                                                         ),
                                                         [DimDate].[Month].[Month].ALLMEMBERS
                                                     ),
                                                     [DimDate].[Year].[Year].ALLMEMBERS
                                                 ),
                                                 [DimDistributionChannel].[Channel].[Channel].ALLMEMBERS
                                             ),
                                             [DimMarketOrganization].[Factory].[Factory].ALLMEMBERS
                                         ),
                                         [DimProductLine].[Code].[Code].ALLMEMBERS
                                     ),
                                     [DimProductLine].[PRODUCT1].[PRODUCT1].ALLMEMBERS
                                 ),
                                 [DimProductLine].[PRODUCT2].[PRODUCT2].ALLMEMBERS
                             ),
                             [DimProductLine].[PRODUCT3].[PRODUCT3].ALLMEMBERS
                         ),
                         [DimProductLine].[PRODUCT].[PRODUCT].ALLMEMBERS
                     ),
                     [DimProductLine].[Product Line Hierarchy].[PL Division].ALLMEMBERS
                 ),
                 [DimProductOrganization].[Organization].[Organization].ALLMEMBERS
             ),
             {
                 [Measures].[Quantity],
                 [Measures].[Sales YTD],
                 [Measures].[Sales]
             }
         ),
         ANCESTOR(
             [DimDate].[Date Hierarchy].CURRENTMEMBER,
             [DimDate].[Date Hierarchy].[Year]
         ).MEMBER_CAPTION,
         BDESC
     )
     PROPERTIES MEMBER_CAPTION, MEMBER_UNIQUE_NAME ON 1
 FROM [xxxxx] CELL PROPERTIES VALUE

Could you please help me with how to convert [DimDate].[Calculation Period].[Calculation Period] to date format (like YYYY+MM+01)

Thanks a lot