Can't get END of current month in YTD context

Hi,

I have this DAX:

VAR SelectedStartDate = STARTOFMONTH(('Date'[Date]))
VAR SelectedEndDate = MAX('Date'[Date])

VAR BudgetDates =
    CALCULATETABLE(
        'Date',
        DATESBETWEEN('Date'[Date], SelectedStartDate, SelectedEndDate),
        'Date'[WorkdayID] = 1
    )

It works fine when I calculate all the BudgetDates in current month.

However, when I want the YearToDate Budget values (using YTD in a filter), SelectedStartDate is right (1st of Jan), but SelectedEndDate becomes the end of Jan (I want the dates between 1st of Jan and the current month).

I tried making SelectedEndDate = Today() or MAX(Date) but it doesn't work.

Any tips?
For Context. this is the whole formula:

VAR FirstMnthDate = STARTOFMONTH('Date'[Date])     
VAR LastMntDate = MAX('Date'[Date]) 
VAR BudgetDates = CALCULATETABLE('Date', DATESBETWEEN('Date'[Date], FirstMnthDate, LastMntDate), 'Date'[WorkdayID] = 1)
VAR BudgetToDivide = CALCULATE(CALCULATE([Budget], 'Date'[Date] = FirstMnthDate), BudgetDates) 
VAR NumOfDays = COUNTROWS(BudgetDates)   
VAR DailyAmount = DIVIDE ( BudgetToDivide, NumOfDays,0)
RETURN CALCULATE(SUMX(VALUES('Date'[Date]), DailyAmount), 'Date'[WorkdayID] = 1)