The Canon site does not list it as a "Recall", it is shown as a "Product Advisories" with the indication they will fix it out-of-warranty IF the problem is caused by the indicated "phenomenon"
Nowhere does it say you should send in properly functioning units at this time under a recall.
Exactly! My S100 starts with 30 which is one of the potentially defective ones. From what I'm reading, you can't send it back unless there is a problem.
"Canon reached out to clarify that it has only issued an advisory about the problem. It's not a full product recall. If you're having problems with the lens, the company will happily fix it, but it's not calling in all of the S100s within the above serial number range."