REGRESSION: Several Microsoft.Network resources missing in 2015-01-01 schema

[StephenWeatherford]

The following used to cause no validation errors:

{
    "$schema": "http://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "location": {
            "type": "string"
        },
        "virtualNetworkName": {
            "type": "string"
        },
        "addressPrefix": {
            "type": "string"
        },
        "subnetName": {
            "type": "string"
        },
        "subnetPrefix": {
            "type": "string"
        }
    },
    "resources": [
        {
            "name": "[parameters('virtualNetworkName')]",
            "type": "Microsoft.Network/virtualNetworks",
            "apiVersion": "2017-08-01",
            "location": "[parameters('location')]",
            "properties": {
                "addressSpace": {
                    "addressPrefixes": [
                        "[parameters('addressPrefix')]"
                    ]
                },
                "subnets": [
                    {
                        "name": "[parameters('subnetName')]",
                        "properties": {
                            "addressPrefix": "[parameters('subnetPrefix')]"
                        }
                    }
                ]
            }
        }
    ]
}

Now the resource type "Microsoft.Network/virtualNetworks" is no longer accepted:

[StephenWeatherford]

Change occurred sometime since around October

[StephenWeatherford]

This schema isn't being kept up anymore, but filing in case it's important that it doesn't regress by removing old resources.

I'm okay if this is closed by design.

The 2019 schema is fine.