Apple has released watchOS 9.0.1 for the Apple Watch Ultra, which won’t even be available until tomorrow.
According to Apple’s release notes, this update includes improvements and bug fixes for your Apple Watch Ultra. For example, audio could be distorted during phone calls using speakers.
Apple Watch Ultra owners can download the update by opening up the Apple Watch app on their iPhone and going to General > Software Update. To install the new software, the Apple Watch needs to have at least a 50% battery charge. Plus, it needs to be placed on a charger, and it needs to be in range of the iPhone.