Does the reg(s) provide specific guidance on how to handle bounced back e-mails. (Prob. cust changed address). We will call cust for new address...but does the reg ask us to have customer follow the same test (to ensure customer can get their e-mail statements are ready message? Or, should we call customer and ask them to sign up again (from the beginning) using their new address, etc. etc. The first scenario is a short cut, taking the emial address over the phone and sending the test, etc....which is the most preferred/used by those of you sending estatements? iIcan't find where the regs tell us how to handles these situations?

Your requirements are to take all reasonable steps to attempt redelivery. If you get a new email address I wouldn't say that, on its face, says there are substantive changes requiring demonstrable consent all over. If the consumer said they no longer had email, you'd revert to snail mail.