Rates that fall out of the parameters could be something bad, or could just be an error. Was the rate entered incorrectly when it was created, or did someone go in and change the rate? Are there a lot of errors, or just a few? Random personnel responsible, or always the same one? These are just a few I could think of. The answers will let you know if you need to investigate more, and if you have a problem on your hands.
As for non-automatic renewels, I've never dealt with these. But I would suggest looking at the procedures to determine what is supposed to be done. Is an official check cut with the proceeds mailed to the depositor? Do the funds stay on deposit at 0% interest? What if the funds are never claimed? Are they escheated?
There's never enough time to do all the nothing you want.