The New York State Department of Taxation & Finance has issued guidance explaining various transitional filing positions for Article 32 and Article 9-A taxpayers affected by the corporate tax reform legislation that became effective for tax years beginning on or after January 1, 2015. Transitional Filing Provisions for Taxpayers Affected by Corporate Tax Reform Legislation, TSB-M-15(2)C (N.Y.S. Dep’t of Taxation & Fin., Feb. 26, 2015). For example, the technical memorandum provides that continuing Article 9-A taxpayers must use new 2015 tax forms, and cautions that returns submitted using prior- year forms will not be processed and will not be considered timely filed. Another example is that the mandatory first installment of estimated tax for 2015 should be based on the tax or properly estimated tax shown on the taxpayer’s 2014 return and should not reflect the 2015 corporate tax reform changes. However, those tax reform changes do have to be taken into account for the second, third, and fourth installments of estimated tax.