We have not seen widespread reports similar to yours, which is why I said it is not a "known" problem.
You may well see the same problem on several of your servers, but that does not mean it is happening on every cPanel server that has been updated. You need to consider what customizations you may have made on all of your affected servers. Yes, you may notice a pattern on your servers, but they may have something in common that is not the same with all cPanel installations that just got an update.
Anytime anything provided by cPanel stops working, especially after an update, please do not hesitate to submit a ticket so that we can investigate the problem, fix it, and if it really is something that is going to cause a widespread problem, we can alert our developers.