The following mutation updates a URL file upload:

```graphql
mutation UpdateURLFileUpload(
  $urlFileUploadId: ObjectID!
  $uploadBaseDomain: String
  $enabled: Boolean
) {
  updateUrlFileUpload(input: {
    urlFileUploadId: $urlFileUploadId
    uploadBaseDomain: $uploadBaseDomain
    enabled: $enabled
  }) {
    urlFileUpload {
      id
      uploadBaseDomain
      enabled
    }
  }
}
```

You can update the following fields:

- `uploadBaseDomain` - change the base domain used for resolving relative URLs.
- `enabled` - enable or disable the upload.
- `projectUploadType` - change the upload type.