Add records for missing dates into the table

Hi! Could someone help to fix this calculation or provide an advice?

There is a large table Production that has Date, Model, Part columns (among others). There is a measure TakeRate that calculates a historical ratio of part per model - this one is working properly. There is also another measure Plan to calculate a Model plan volume per Date that is located in another table, also working correctly. The calculation that fails is called Estimate and it multiplies TakeRate by Plan and aggregates within Production table - rows roll-up is needed as TakeRate produces wrong results at a higer level due to a nature of this calculation. Now, the problem is that Production table doesn't have records for all dates for each Part and Model combination, so Plan for these dates is not included into a calculation.

Estimate = 
   VAR PartModels = 
   //ADDMISSINGITEMS( 'Date'[MonthDate], 'Model'[model],
   SUMMARIZE( 
        Production,
        'Date'[MonthDate],
        'Model'[model],
        Production[part_no])
    //, 'Date'[MonthDate], 'Model'[model])

    VAR RollUp = 
     SUMX( PartModels,
        [Plan] * [TakeRate]
    )
RETURN RollUp