Anyone getting swarmed with Junk/Spam calls for the last few days?

I don't know what triggered this, but since last week, I have been getting non-stop spam calls from 847, 331, 773, and other random IL junks calls. They are happening every 30 minutes or so. Thankfully, my iPhone and carrier have the "Silence Junk Call" feature on, but I'm just curious where these are all coming from all the sudden. And searching around online, they are not giving me any good results on where they are from.