Creating a Calendar for Each Account ID with Revenue Calculation per Account at Point in Time

Worked like a charm. Ended up with the following formulas for the table and to summarize ARR for each line.

Customer Monitoring =
GENERATE (
    'Calendar',
    SUMMARIZE (
        FILTER (
            'Account For Opps',
            'Account For Opps'[HasOpp] = TRUE
        ),
        'Account For Opps'[Id]
    )
)

ARR = 
CALCULATE (
    SUM ( Opportunity[Amount (ARR (USD))] ),
    FILTER (
        Opportunity,
        Opportunity[Type] = "New Business"
            || Opportunity[Type] = "New Business Crossell"
            || Opportunity[Type] = "Add-On"
            || Opportunity[Type] = "Upgrade"
            || Opportunity[Type] = "Existing Business"
            || Opportunity[Type] = "Downgrade"
            || Opportunity[Type] = "Churn"
    ),
    FILTER (
        Opportunity,
        Opportunity[Mapped Stage] = "Won"
            || Opportunity[Mapped Stage] = "Won (Downgrade)"
    ),
    FILTER (
        Opportunity,
        Opportunity[CloseDate] <= 'Customer Monitoring'[FullDateAlternateKey]
    ),
    FILTER (
        Opportunity,
        Opportunity[AccountId] = EARLIER('Customer Monitoring'[Id])
    )
)