Also various Apple systems define CFBundleShortVersionString to be of the format A.B.C, no fourth element allowed. macOS versioning is still stuck with 10 as th

Also various Apple systems define CFBundleShortVersionString to be of the format A.B.C, no fourth element allowed. macOS versioning is still stuck with 10 as the A, B identifies the major release and C is the point release that is effectively also marketing driven. With iOS the first number is used for the major releases so C is available for bug fixes.