Avoiding Circular Discrepancies for Col A = Col B (last row) and Col B = Col A (current row)?

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1. In the future, please upload an attachment instead; I spent quite a while copying from it.
2. The difficult part is writing the measure of "01_Beginning Inventory". I have provided compatibility for various time dimensions (daily, weekly, monthly, quarterly, semi-annually, and annually) of the measure.
3. Note that your "Current Inventory" table should include a date dimension.
4. Essentially, there are only inbound and outbound operations. Initial, final, and inventory values are derived from these, so the model should be designed with this logic in mind.

01_Beginning Inventory = 
VAR DATE_START0 =
    CALCULATE ( FIRSTDATE ( 'Calendar'[dates] ), ALL ( 'Calendar' ) )
VAR DATE_END0 =
    LASTDATE ( 'Calendar'[dates] )
VAR TF0 =
    HASONEVALUE ( 'Calendar'[dates] ) //日
VAR TF1 =
    HASONEVALUE ( 'Calendar'[YearWeek] ) //周
VAR TF2 =
    HASONEVALUE ( 'Calendar'[YearMonth] ) //月
VAR TF3 =
    HASONEVALUE ( 'Calendar'[YearQuarter] ) //季度
VAR TF4 =
    HASONEVALUE ( 'Calendar'[YearHalf] ) //半年度
VAR TF5 =
    HASONEVALUE ( 'Calendar'[FY00] ) //年度
VAR N0 =
    SWITCH (
        TRUE (),
        TF0, 0,
        TF1,
            DATEDIFF (
                FIRSTDATE ( 'Calendar'[StartOfWeek] ),
                LASTDATE ( 'Calendar'[EndOfWeek] ),
                DAY
            ),
        TF2,
            DATEDIFF (
                FIRSTDATE ( 'Calendar'[StartOfMonth] ),
                LASTDATE ( 'Calendar'[EndOfMonth] ),
                DAY
            ),
        TF3,
            DATEDIFF (
                FIRSTDATE ( 'Calendar'[StartOfQuarter] ),
                LASTDATE ( 'Calendar'[EndOfQuarter] ),
                DAY
            ),
        TF4,
            DATEDIFF (
                FIRSTDATE ( 'Calendar'[StartOfHalfYear] ),
                LASTDATE ( 'Calendar'[EndOfHalfYear] ),
                DAY
            ),
        TF5,
            DATEDIFF (
                FIRSTDATE ( 'Calendar'[StartOfYear] ),
                LASTDATE ( 'Calendar'[EndOfYear] ),
                DAY
            ),
        0
    ) + 1
VAR DATE_END1 =
    SWITCH (
        TRUE (),
        TF0, DATEADD ( DATE_END0, - N0, DAY ),
        TF1, DATEADD ( LASTDATE ( 'Calendar'[EndOfWeek] ), - N0, DAY ),
        TF2, DATEADD ( LASTDATE ( 'Calendar'[EndOfMonth] ), - N0, DAY ),
        TF3, DATEADD ( LASTDATE ( 'Calendar'[EndOfQuarter] ), - N0, DAY ),
        TF4, DATEADD ( LASTDATE ( 'Calendar'[EndOfHalfYear] ), - N0, DAY ),
        TF5, DATEADD ( LASTDATE ( 'Calendar'[EndOfYear] ), - N0, DAY ),
        DATE_START0 //无筛选的时，默认日期表期初。
    )
VAR DATE_END2 =
    IF ( ISBLANK ( DATE_END1 ), DATE_START0, DATE_END1 ) //兼容 dateadd 后的空值，注意日期表的两个端点。
VAR DATE_TABLE0 =
    DATESBETWEEN ( 'Calendar'[dates], DATE_START0, DATE_END2 )
VAR IN0 =
    CALCULATE ( [02_Receipts], DATE_TABLE0 )
VAR OUT0 =
    CALCULATE ( [03_Forecast], DATE_TABLE0 )
RETURN
    IF ( [03_Forecast], IN0 - OUT0, BLANK () )

02_Receipts = 
SUM ( 'Current Inventory'[Current Inventory] ) + SUM ( 'Receipts'[QTY] ) + 0

02_Receipts_Display = 
IF ( [03_Forecast], [02_Receipts], BLANK () )

03_Forecast = 
SUM ( Forecast[QTY] )

04_Ending Inventory = 
VAR DATE_START0 =
    CALCULATE ( FIRSTDATE ( 'Calendar'[dates] ), ALL ( 'Calendar' ) )
VAR DATE_END0 =
    LASTDATE ( 'Calendar'[dates] )
VAR DATE_TABLE0 =
    DATESBETWEEN ( 'Calendar'[dates], DATE_START0, DATE_END0 )
VAR IN0 =
    CALCULATE ( [02_Receipts], DATE_TABLE0 )
VAR OUT0 =
    CALCULATE ( [03_Forecast], DATE_TABLE0 )
RETURN
    IF ( [03_Forecast], IN0 - OUT0, BLANK () )

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