I used Turbo Tax Premier for my 2016 Federal and California State tax filing. I just realized a huge error when I filled out the questionaire last year. I didn't select that I had income from New York in the personal information tab, so when I attempted to file the New York non-resident state tax, Turbo Tax told me my situation didn't require the New York non resident return to be filled out. I think this was due to Turbo Tax using my 2015 information, which had New York as a source of income, but I didn't see that I had to update the income from other states part of the personal information. Is amending as simple as selecting the amend my return for 2016, update the personal information part, purchase the 2016 New York state return ($44.99), have Turbo Tax 2016 complete the New York nonresident, then Turbo Tax will amend my 2016 California resident State return? There shouldn't be any amendment to the 2016 Federal that I can see. Thank you!