Hi @fc00::/7 ,
I tell you what I think:
The show run command shows you the settings in a general way.
For example, it shows you the general settings of an interface, but to see more details you need the show int command.
In the case of the IOS version, it shows you only the release numbers (16.3)
To see the details of the maintenance number of that version (16.3.7) and the special release letter, if there was, you must go to the show version command.
I leave this blog of the community for more details of the numbers of your version:
https://community.cisco.com/t5/networking-blogs/all-you-need-to-know-about-cisco-ios-xe-16-x-releases/ba-p/3661814
Regards