Ah!  How to check which versions of BOINC are available?  From that page, they offered the example:
	Code:
	sudo apt-cache madison ^apache2
 Not sure what madison means in this context.  But I tried replacing ^apache2 with boinc, and I get this:
	Code:
	sudo apt-cache madison boinc
     boinc | 7.16.6+dfsg-1 | http://archive.ubuntu.com/ubuntu focal/universe amd64 Packages
     boinc | 7.16.6+dfsg-1 | http://archive.ubuntu.com/ubuntu focal/universe i386 Packages
 Does this mean that the only available version is 7.16.6, which is the version I am running?  Or do I need to change the query somehow?