Change Blox Dynamic Pivot Table Header

I have created a Blox Dynamic Pivot Table that I have transposed so that the columns are months and the rows are calculated values. I would now like to update the table so that the month displayed in each column is actually the next month (e.g., April 2023 should read May 2023). This way I can label the table "Counts at start of Month". 

Does anyone know how to map the column header values to be the previous month's text? Thanks!

I followed this template to create the pivot table https://community.sisense.com/t5/knowledge/blox-template-dynamic-pivot-tabl/ta-p/8673.

I use this code to pivot transpose the table https://community.sisense.com/t5/knowledge/transposed-pivot-table-with-blox/ta-p/9522.

Attached is the editor view of the table.

Below is my Blox code

{
    "style": "",
    "disableLazyLoading": true,
    "script": "",
    "title": "",
    "showCarousel": false,
    "body": [
        {
            "spacing": "default",
            "type": "Container",
            "style": {
                "padding": "5px"
            },
            "items": [
                {
                    "type": "Column",
                    "items": [
                        {
                            "type": "ColumnSet",
                            "columns": [
                                {
                                    "type": "Column",
                                    "items": [
                                        {
                                            "spacing": "default",
                                            "type": "Container",
                                            "color": "default",
                                            "horizontalAlignment": "left",
                                            "style": {
                                                "color": "#5a6cb2",
                                                "padding-top": "10px",
                                                "padding-bottom": "10px"
                                            },
                                            "items": [
                                                {
                                                    "type": "TextBlock",
                                                    "text": "{panel:Service Month} ",
                                                    "style": {
                                                        "color": "#5a6cb2",
                                                        "font-weight": "bold",
                                                        "font-size": "14px",
                                                        "margin-left": "auto",
                                                        "margin-right": "auto"
                                                    }
                                                }
                                            ]
                                        },
                                        {
                                            "type": "ColumnSet",
                                            "columns": [
                                                {
                                                    "type": "Column",
                                                    "style": {
                                                        "flex-direction": "row"
                                                    },
                                                    "items": [
                                                        {
                                                            "type": "TextBlock",
                                                            "text": "{panel:Active Members} ",
                                                            "horizontalAlignment": "left",
                                                            "size": "medium",
                                                            "style": {
                                                                "color": "#54565a",
                                                                "padding-top": "5px",
                                                                "padding-bottom": "5px",
                                                                "margin": "auto",
                                                                "font-size": "14px"
                                                            }
                                                        }
                                                    ]
                                                }
                                            ]
                                        },
                                        {
                                            "type": "ColumnSet",
                                            "columns": [
                                                {
                                                    "type": "Column",
                                                    "style": {
                                                        "flex-direction": "row"
                                                    },
                                                    "items": [
                                                        {
                                                            "type": "TextBlock",
                                                            "text": "{panel:MoM Growth} ",
                                                            "horizontalAlignment": "left",
                                                            "size": "medium",
                                                            "style": {
                                                                "color": "#54565a",
                                                                "padding-top": "5px",
                                                                "padding-bottom": "5px",
                                                                "margin": "auto",
                                                                "font-size": "14px"
                                                            }
                                                        }
                                                    ]
                                                }
                                            ]
                                        }
                                    ]
                                }
                            ]
                        }
                    ]
                }
            ]
        }
    ]
}