Welcome to the community 
When you receive your phone, you should check the current patch level under Settings â About phone â Android version â Android security update (or run adb shell getprop ro.build.version.security_patch).
In the case of the latest stock FPOS A.163 you would have a security patch level of 2022-08-05.
Now you can, for example, check if BoardConfig.mk in the CalyxOS sources has been updated recently, as you can see the default branch is at 2022-07-05 at the moment, so you are definitely not getting the latest version.
You should check the patch level of the Calyx images you download as well, or just ask in the forum, someone is probably already running the latest version 