The Galaxy Watch4 and 4 Classic still have a few days to go before reaching their new owners. However, that has apparently not stopped them from receiving an OTA update already. This new firmware is rated to optimize stability and performance on the new wearables as they start to go to work tracking a user's health.
https://www.notebookcheck.net/Samsung-s-Galaxy-Watch4-series-gets-its-first-software-update-prior-to-even-hitting-the-market-yet.556386.0.html