Thanks for pointing the error message. We will look into it.
There is no need to take any more actions, your update is successful and complete. The Wi-Fi firmware for your hardware has not changed since P02-08. If you want to confirm, choose the WiFi tab in USB/Serial Utilties, then click on the "Advanced Settings" tab. You'll see the WiFi firmware version listed. If it says "A4.0.4", it is already current.