Filter timestamp based on condition and previous value

Hi slown_surelearn 

Yes, since you're using DirectQuery mode, you cannot use Power Query (M language) for transformations. However, you can achieve this in DAX within Power BI.

You can create a mesure to find the change time date to when the team changes ALPHA to BETA.

First_Change_To_Beta =
VAR PreviousAlphaDate =
    CALCULATE(
        MAX('Table'[CHANGE_DATE_TIME]),
        'Table'[Responsable team] = "Alpha",
        'Table'[CHANGE_DATE_TIME] < 
            MINX(
                FILTER('Table', 'Table'[Responsable team] = "Beta"),
                'Table'[CHANGE_DATE_TIME]
            )
    )
VAR FirstBetaDate =
    CALCULATE(
        MIN('Table'[CHANGE_DATE_TIME]),
        'Table'[Responsable team] = "Beta",
        'Table'[CHANGE_DATE_TIME] > PreviousAlphaDate
    )
RETURN
    FirstBetaDate

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