Script file super easy to do, just do as it says
making a bootable BS info
run app=ReInstall, WIFI CONNECTION NEEDED!!
Createinstallmedia on my Late 2011 Macbook pro
boots to installer
All I did was rename SystemVersion.plist
I made it /System/Library/SystemVersion1.plist
now to do same with others
Running BIG_SUR app opens it and makes a re-intstall
Right script file Is up!!