It shouldn't matter who is the primary taxpayer. You have to make sure though that all the questions about each taxpayer are answered correctly. It might be possible if you are switching the primary taxpayer that some background question might be carried over incorrectly. Go through the interview questions one by one for each taxpayer to make sure all the questions are answered correctly.
Otherwise, I don't really know. Is one of you 65 or older...or became 65 this year?
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