I've joined the Faithlife Group "Read Calvin's Institutes in 2015". I tried to Connect to the reading plans that Doc B created, but I get an error message when I try:

Also note that there's a grammatical error in the error message. It reads: "There was an error connected to your group reading plan. Please try again later." I think it meant to say "There was an error connecting to your group reading plan. Please try again later." Yes "connected to" makes grammatical sense (meaning "related to") but I think in the context, when I'm trying to "Connect" via the "Connect" button, it was trying to say there was an error with that connect process, thus "connecting to..." was meant.
EDIT: Now that I've clicked "OK" on those two error messages (and the third one after I tried to connect and got the same error message), I see that Doc B was probably at work on the reading plans and deleted those other three, because there's a new one now that I was able to connect to:

So maybe that's the explanation for the error message. Still, it could have been more informative: "The reading plan you are trying to connect to has been deleted." Try again later won't work in that case. Thanks!