Unifi-Network-Application: Migration appdata note

docs/sandbox/apps/unifi-network-application.md

@@ -9,7 +9,7 @@
 | [:material-home: Project home](https://www.ui.com/download/unifi/){: .header-icons } | [:octicons-link-16: Docs](https://github.com/linuxserver/docker-unifi-network-application/blob/main/README.md){: .header-icons } | [:octicons-mark-github-16: Github](https://github.com/linuxserver/docker-unifi-network-application){: .header-icons } | [:material-docker: Docker](https://hub.docker.com/r/linuxserver/unifi-network-application){: .header-icons }|
 
 !!! Warning
-    This role is a replacement for the previous Unifi Controller role. This is not an in-place replacement. In order to migrate, you must perform a full backup from the Unifi web interface, and restore from that backup when running the setup wizard in a fresh instance of the Unifi Network Application.
+    This role is a replacement for the previous Unifi Controller role. This is not an in-place replacement. In order to migrate, you must perform a full backup from the Unifi web interface, and restore from that backup when running the setup wizard in a fresh instance of the Unifi Network Application. You must rename/remove the previous appdata from `/opt/unifi` before deploying the Unifi Network Application role.
 
 ### 1. Installation