As long as no excess Roth IRA contribution was made when MAGI is determined correctly, this bug is of no consequence. It's only of consequence if the incorrectly determined MAGI leads one to believe that there was no excess Roth IRA contribution when there actually was and as a result the individual does not know that they need to timely correct the excess to avoid a penalty. Also, given the conditions required to trigger the bug, probably only a small percentage of TurboTax users would ever be exposed to the bug, so it might not end up all that high on the priority list. I would suspect that TurboTax prioritizes such things based on how much they might have to pay out under their calculation guarantee.
