DAX handling Blank differently on two different servers

[rloski-public]

I have a report that runs against an SSAS tabular (2019 Standard).  It includes measures defined in the report.  I have gotten the DAX query and run the query against our development and production server and get different results on two measures (the second depends on the first, so I will only discuss the first).

The first measure is [YTD Growth] which subtracts [YTD Sales]-[PY YTD Sales] (Year to date sales and prior year YTD sales).   The query shows both [YTD Sales] and PY YTD Sales] and the values match.  Since it is early in the year, one or both values are blank.

[YTD Sales] is defined in the SSAS model and is defined TOTALYTD('Sales'[Sales],'Date'[Date]) 

[PY YTD Sales] is defined in the report and is defined  CALCULATE([YTD Sales],SAMEPERIODLASTYEAR('Date'[Date])

On development [YTD Growth] is blank, on production, [YTD Growth]  has the expected value (treating blank as zero if YTD Sales or PY YTD Sales has a value and blank if both are blank).

What should I look for to account for this discrepency?  

Development is version 15.0.32.62 and production is version 15.0.35.51.

[rloski-public]

Just a little additional information.

The following query evaluates to 1 on Development and Production.

EVALUATE {1 + BLANK()}

[rloski-public · Accepted solution]

I ran an update on the development SQL Server to bring it up to date.  The issue no longer occurs.

My thought is that for the particular version of SSAS I was using it was not handling the transition from in model measures to in report measures (sorry, I don't know the proper terms.)