Calculate with visual filter looses date context

Hi

I'm trying to create a running total to be evaluated for a specific period. The measure is applied in a stacked chart which has YYYYMM as x axis where continous x axis is disabled. The formula is based on a date table and a transaction table. It works until I apply a legend, or categorization, by location from the transaction table. Then the date table is disregarded and powerbi chooses the date column in the transaction table as a date table, which is unfortunate as it's incomplete.

E.g. filtering for all dates from last date in november - 14 days suddenly becomes last transaction date for location -14 days once location is added as a filter.

Does anyone have any idea why this happens and what I can do with it?

E.g.

EVALUATE
ROW (
    "gfdsfg", 
      CALCULATE (
        CALCULATE (
            LASTDATE ( L_Datetable[DateKey] ),
            FILTER (
                ALL ( L_Datetable ),
                L_Datetable[DateKey]> ( MAX ( L_Datetable[DateKey] ) - 14 )&& L_Datetable[DateKey] <= MAX ( L_Datetable[DateKey] )
            )
        ),
        L_Datetable[YearMonth] = 201611,
        S_BSAK[Location] = "1"
    )
)

yields the last transaction for location 1, 01.11.2016,  (DD.MM.YYYY) where the outer calculate represent the filter applied in the chart as legend. It actually uses the daterange 01.11.2016 to 01.11.2016-14d instead of using the asked 15.11.2016 to 15.11.2016-14d range. Hence it ends up with 01.11.2016

While mashing it all in one calculate works as expected:

EVALUATE
ROW (
    "gfdsfg"; 
        CALCULATE (
            LASTDATE ( L_Datetable[DateKey] );
            FILTER (
                ALL ( L_Datetable );
                L_Datetable[DateKey]> ( MAX ( L_Datetable[DateKey] ) - 14 )&& L_Datetable[DateKey] <= MAX ( L_Datetable[DateKey] )
            )
        ;
        L_Datetable[YearMonth] = 201611;
        S_BSAK[Location] = "1")
)

Which returns blank (i.e. no transactions as the max date in the date table is 15.11.2016-14d=01.11.2016, and hence no transactions fits as the first one is 01.11.2016, and the filter is bigger than)

Any tips and tricks are much appreciated!