Customers who purchase one of the new M3, M3 Pro, or M3 Max MacBook Pro or iMac models will need to install a macOS Sonoma update after receiving their machines.
The Macs will ship with a custom version of macOS Sonoma 14.1 with a build number of 23B2073, but new users will need to download and install a new version with a build number of 23B2077.
Day one updates are not unusual for new devices as Apple often has to begin manufacturing with an older version of the software. Apple first released macOS Sonoma 14.1 on Wednesday, October 25, and the current version has a build number of 23B74.
Read more at MacRumors.com