Retrieve the Lastest Available Allocation when Month is Zero

Hi swwong1,
Thank you for reaching out to the Microsoft fabric community forum. Thank you Irwan Ashish_Excel  for your input on this issue. 
After thoroughly reviewing the details you provided, I was able to reproduce the scenario.

Dax Measure:

Final Allocation Excluding Novak = 
CALCULATE(
    SUMX(
        SUMMARIZE(
            FILTER(
                fTransaction,
                fTransaction[Salesperson] <> "Novak"
            ),
            fTransaction[Salesperson],
            fTransaction[Project],
            'dDate'[Month Name],
            "Alloc", MAX(fTransaction[Allocation])
        ),
        [Alloc]
    )
)

Output: 

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Thank you.