macOS Recovery: No option to upgrade to Big Sur

Hi everyone,

I'm trying to install macOS Big Sur on a separate APFS volume. I've backed up my Mac and created the new volume, but when I start up in macOS Recovery via Option–Command–R, there's no option to upgrade to Big Sur – only the option to install Catalina.

I think this is a known issue (Command–R should allow you to re-install your current version of macOS while Option–Command–R should allow you to upgrade to the latest version), so which workaround should I use?

Will installing via > System Preferences give me the option to choose which disk I want to install to? If not, is there another workaround?

Thanks!