http://wccftech.com/watchos-4-0-1-download-for-apple-watch-release-with-lte-fix/

Apple has released watchOS 4.0.1 for Apple Watch. This update is primarily aimed towards Series 3 users and fixes an issue pertaining to how LTE and WiFi networks are managed.

Apple has pushed out the first ever update to its watchOS 4 firmware for Apple Watch. The new firmware update addresses an issue that was plaguing some Apple Watch Series 3 users. This caused the wearable to connect to open WiFi networks whenever the user was nearby, disrupting LTE connectivity altogether in some cases.