@sltxdad , I personally know at least 7 or 8 people off the top of my head that are currently attending or had the option of attending their WL college (Cornell, UPenn, Vanderbilt and WashU). OTOH, I do not know anyone personally who has ever been struck by lightning.
I would assume the OP has or is in the process of choosing a May 1 school from her acceptances, she would simply like to keep her options open. I think at this point most of us on the WL know we have to pick something. It does not mean that we cannot aspire to something more. Therefore, the forget about the WL advice is not too helpful.
To the OP, assuming you would attend WLs 2 and 3, absolutely update and say you are very interested but of course do not say you would attend no matter what if not true. They want to hear from you and make sure you are still really interested in them. Maybe you moved on. Absolutely update even about minor things. For two reasons, first it gives the Rep something to say, when they advocate for you and shows you are still serious about school and are not goofing off.