# Migration: 1.27.1 to 1.28.0

Only code that reads the region tree (`RegionsService.getRegions`) needs to change anything.

## 1. Upgrade

```sh
pnpm add @v-office/sdk-core@1.28.0
```

## 2. Region ids are keys now

1. A region's `id` and `parentId` change on v10 from the websites service's id to the
   region's key (`dornum`). Anything that stored or linked an old id, such as a `?region=`
   value, a region page URL or a saved reference, no longer matches the tree: replace it
   with the key.
2. Replace a region's `slug` or `path` with its `id`. A region has no `description` any more.