I also called the IRS this morning and the rep said that a CP 30 Notice will be coming out explaining the checks but that their system found that the self imposed penalties were incorrect because the taxpayers had an overpayment.  My clients did not have an overpayment and she also said that the penalty was computed on 110% and they recomputed it on 100% - but the AGI is well over $150K from the prior year.  The math looks correct from my end unless there was a tax law change we are unaware of.  No one seems to know at the IRS.  I expect more checks and letters.