Ok, so this may sound really dumb, but I've been saying this for years and the Dr's think I'm nuts. It does happen to me on a fairly regular basis. It's almost like I'm on some kind of a cycle. I will go three weeks or so where my BG readings are great, seems like I can eat anything, then for no noticeable reason whatsoever, I will struggle for about a week (even over a couple of pods). The readings just fluctuating, even when I diligently measure carbs accurately - lots of corrections, lots of testing. Then for no reason (and as if by magic) we are back to steady readings again. It's been happening a long time, even when on MDI. The bads are adjustable though, in that corrections do bring it down after a while, it's just not easy. It has been much easier with the pump because of the ease of correcting, but still a mystery to me. Not sure this helps you a lot dishers, but you're not alone, for sure.