https://support.apple.com/en-us/102655
> On an Intel-based Mac:
> If you used Command-R to start up from the local Recovery system, you get the current version of the most recently installed macOS.
> If you used Option-Command-R to start up from Internet Recovery, you might get the latest macOS that is compatible with your Mac.
> If you used Shift-Option-Command-R to start up from Internet Recovery, you might get the macOS that came with your Mac, or the closest version still available.