Missing deployment targets in Xcode 12.4

I am also curious about this. Same Xcode and macOS versions. I have 11.4 and 12.1 listed in my deployment targets but not 12.0. I would like to set 12.0 as my minimum supported OS but I am concerned because it isn't listed.

Just stumbled upon this myself. I know I have recently created fresh projects and set the deployment to 14.0. I want to say it was with earlier Xcode 12.x versions?

Anyhow, I haven't done any testing with such a setting, but you can select 'Other' and type in a version. e.g. 14.0 or 12.0

Still, it's curious as to why Apple is hiding those initial versions. Perhaps those OS versions are not recommended to have anymore? e.g. enough serious issues found where they are hoping developers will just target the dot versions instead. Just a guess.

For me, I'll just pick 14.1 for my new projects. By the time I'm done, iOS 15 release will be right around the corner.

For iOS 12.0, I see no problems in requiring 12.1 or even 12.3. The quantity of iOS 12 years is very small and for those that cannot update past 12.x, I would assume they'd probably at least be applying all the security and other updates.