<p>First of all, you don’t have to worry about the tax deadline because you have already e-filed, on time. What you would have to do for any changes is file an amended return, and there is no deadline for that (or at least not one coming up soon). </p>
<p>I used to have my taxes done by a CPA, and the main reason I was willing to pay the CPA $$$ to file return was so that HE was the one who dealt with all the problems, including fixing his own mistakes, if any. </p>
<p>It seems to me that any reputable firm, having prepared your return in a way they now believe to be inappropriate, would take responsibility for preparing the return correctly, including preparing and filing an amended return, without additional charge to you. It was their mistake, not yours – so therefore it becomes their responsibility to fix it.</p>
<p>Three days before the filing deadline is probably NOT the best time to talk to them about this, though. Ask them to file an extension request for your son (it’s ok if that gets filed on Monday instead of Friday, as Friday April 15th is a federal holiday for a weird convoluted reason) – and then next week ask to talk to someone who is a supervisor at the office to get it all straightened out.</p>