Browse API category tree arrangement

[shipscript]

developer_support@ebay 

I would like to reconstruct the category tree (breadcrumbs) returned by the Browse API. Please help me understand the logic in the ordering of the category tree below.  If there are two leaf categories, then the two leaves are the first two elements, but what is going on with the branches?

•  [A1] Cameras & Photo > [A2] Camera Drones
•  [B1] Toys & Hobbies > [B2] Radio Control & Control Line > [B3] RC Model Vehicles & Kits > [B4] Other RC Model Vehicles & Kits

            "leafCategoryIds": [
                "179697",
                "182186"
            ],
            "categories": [
                {
                    "categoryId": "179697",
                    "categoryName": "Camera Drones"			// A2
                },
                {
                    "categoryId": "182186",
                    "categoryName": "Other RC Model Vehicles & Kits"	// B4
                },
                {
                    "categoryId": "2562",
                    "categoryName": "Radio Control & Control Line"	// B2
                },
                {
                    "categoryId": "220",
                    "categoryName": "Toys & Hobbies"   			// B1
                },
                {
                    "categoryId": "625",
                    "categoryName": "Cameras & Photo"			// A1
                },
                {
                    "categoryId": "182181",
                    "categoryName": "RC Model Vehicles & Kits"		// B3
                }
            ],

•  [A1] Cameras & Photo > [A2] Camera Drones
•  [B1] Toys & Hobbies > [B2]  Radio Control & Control Line > [B3] RC Model Vehicles & Kits > [B4] Quadcopters & Multicopters

            "leafCategoryIds": [
                "179697",
                "182185"
            ],
            "categories": [
                {
                    "categoryId": "179697",
                    "categoryName": "Camera Drones"			A2
                },
                {
                    "categoryId": "182185",
                    "categoryName": "Quadcopters & Multicopters"	B4
                },
                {
                    "categoryId": "2562",
                    "categoryName": "Radio Control & Control Line"	B2
                },
                {
                    "categoryId": "220",
                    "categoryName": "Toys & Hobbies"			B1
                },
                {
                    "categoryId": "625",	
                    "categoryName": "Cameras & Photo"			A1
                },
                {
                    "categoryId": "182181",
                    "categoryName": "RC Model Vehicles & Kits"		B3
                }
            ],

[shipscript]

developer_support@ebay 

I am in the process of migrating a whole bunch of seller tools from the Finding/Shopping APIs to the Browse API.

But I am stumped by the category list. There appears to be a consistent order for category lists on items that include only a single category, which is then lost on a multi-category item.

Here is an example:

https://api.ebay.com/buy/browse/v1/item_summary/search?q=386907492794

Is there a planned arrangement to the category structure that is returned by the Browse API when 2 categories are involved, or am I seeing some sort of API shortcoming here? 

//  Books & Magazines > Books
//  267 > 261186 
//  Sporting Goods > Team Sports > Football > Training Aids  
//  888 > 159049 > 261242 > 159119  

      "leafCategoryIds": [
        "261186",
        "159119"
      ],
      "categories": [
        {
          "categoryId": "261186",
          "categoryName": "Books"
        },
        {
          "categoryId": "159119",
          "categoryName": "Training Aids"
        },

        {
          "categoryId": "159049",
          "categoryName": "Team Sports"
        },
        {
          "categoryId": "888",
          "categoryName": "Sporting Goods"
        },
        {
          "categoryId": "267",
          "categoryName": "Books & Magazines"
        },
        {
          "categoryId": "261242",
          "categoryName": "Football"
        }
      ],