I just manually changed the Gemfile to 3.1.0.rc1 and fixed things that broke. My next step is to fixup my morass of CSS and JS files to use the Asset pipeline

I just manually changed the Gemfile to 3.1.0.rc1 and fixed things that broke. My next step is to fixup my morass of CSS and JS files to use the Asset pipeline correctly. That's probably another hour or so.