Switch Calculation with Multiple conditions

Hi, 

To get the maximum date for each group, you can use the MAX function within a CALCULATE statement to ensure you get the maximum date for each Bay_Code_No group. Here’s an updated version of your DAX formula:

Next 60 min Block Date = 
SWITCH(
    TRUE(),
    'EXTR_STG_FOCUS APPOINTMENTS'[Bay_Code_No] = "BAY 1" && 
    ('EXTR_STG_FOCUS APPOINTMENTS'[Duration] = -60 || 'EXTR_STG_FOCUS APPOINTMENTS'[Duration] = -120), 
    FORMAT(
        CALCULATE(
            MAX('EXTR_STG_FOCUS APPOINTMENTS'[STARTDATE]), 
            'EXTR_STG_FOCUS APPOINTMENTS'[Bay_Code_No] = "BAY 1",
            'EXTR_STG_FOCUS APPOINTMENTS'[Duration] IN {-60, -120}
        ),
        "DD Mmmm YYYY"
    ),
    
    'EXTR_STG_FOCUS APPOINTMENTS'[Bay_Code_No] = "BAY 2" && 
    ('EXTR_STG_FOCUS APPOINTMENTS'[Duration] = -60 || 'EXTR_STG_FOCUS APPOINTMENTS'[Duration] = -120 || 'EXTR_STG_FOCUS APPOINTMENTS'[Duration] = -180), 
    FORMAT(
        CALCULATE(
            MAX('EXTR_STG_FOCUS APPOINTMENTS'[STARTDATE]), 
            'EXTR_STG_FOCUS APPOINTMENTS'[Bay_Code_No] = "BAY 2",
            'EXTR_STG_FOCUS APPOINTMENTS'[Duration] IN {-60, -120, -180}
        ),
        "DD Mmmm YYYY"
    ),
    
    'EXTR_STG_FOCUS APPOINTMENTS'[Bay_Code_No] = "BAY 3" && 
    'EXTR_STG_FOCUS APPOINTMENTS'[Duration] = -60, 
    FORMAT(
        CALCULATE(
            MAX('EXTR_STG_FOCUS APPOINTMENTS'[STARTDATE]), 
            'EXTR_STG_FOCUS APPOINTMENTS'[Bay_Code_No] = "BAY 3",
            'EXTR_STG_FOCUS APPOINTMENTS'[Duration] = -60
        ),
        "DD Mmmm YYYY"
    ),
    
    'EXTR_STG_FOCUS APPOINTMENTS'[Bay_Code_No] = "BAY 4" && 
    'EXTR_STG_FOCUS APPOINTMENTS'[Duration] = -60, 
    FORMAT(
        CALCULATE(
            MAX('EXTR_STG_FOCUS APPOINTMENTS'[STARTDATE]), 
            'EXTR_STG_FOCUS APPOINTMENTS'[Bay_Code_No] = "BAY 4",
            'EXTR_STG_FOCUS APPOINTMENTS'[Duration] = -60
        ),
        "DD Mmmm YYYY"
    ),
    
    'EXTR_STG_FOCUS APPOINTMENTS'[Bay_Code_No] = "BAY 5" && 
    'EXTR_STG_FOCUS APPOINTMENTS'[Duration] = -60, 
    FORMAT(
        CALCULATE(
            MAX('EXTR_STG_FOCUS APPOINTMENTS'[STARTDATE]), 
            'EXTR_STG_FOCUS APPOINTMENTS'[Bay_Code_No] = "BAY 5",
            'EXTR_STG_FOCUS APPOINTMENTS'[Duration] = -60
        ),
        "DD Mmmm YYYY"
    ),
    
    IF(
        ISBLANK('EXTR_STG_FOCUS APPOINTMENTS'[STARTDATE]),
        FORMAT(MAX('EXTR_STG_FOCUS APPOINTMENTS'[STARTDATE]) + 1, "DD Mmmm YYYY"),
        ""
    )
)