A firmware upgrade is not required for the Home Assistant SkyConnect at this point. There are no known bugs with the firmware it ships with.
We're working on making firmware updates available via Home Assistant. You will receive updates automatically in the future.
SL Web Tools to flash firmware updates from the browser
If you want to have the latest update now: you can use the web-flasher below to install the latest firmware version for Home Assistant SkyConnect directly from your browser over USB. You can also use the web-flasher to flash the Zigbee firmware again if you've previously used the experimental multi-protocol support.
To read more about the SL Web Tools, refer to this blog post.