Whenever updating firmware via a WiFi connection, the router administrator should be warned up-front about losing the connection to the router when it reboots. Often when the WiFi computer being used for the firmware update loses the connection to the rebooting router, it may well connect to another WiFi network. From that other network, the router being updated is almost definitely not available so it appears as if the firmware update bricked the router, when in fact, all is well. An up-front warning that this might happen would be nice.
I think it is normal for Wi-Fi client to re-associate to different available wireless network(s) when it lost connection to the existing wireless network. It should be an expected Wi-Fi roaming behaviour on every Wi-Fi client.
However, I do agree that the “Warning Message” should inform user that the router will reboot once the new firmware completed the uploading process, in addition to “Backup device configuration” reminder. I will send this request to our Engineering Team for further review.
Thank you for your suggestion.