(a)    Where necessary, an amended return must be filed in order to report additional income and pay any additional tax due, or claim a refund of tax overpaid, subject to the requirements, limitations, or both, contained in Sections 187.29(b) and (c), 187.30, 187.31, 187.32 and 187.33. Such amended return shall be on a form obtainable on request from the Administrator. A taxpayer may not change the method of accounting or apportionment of net profits after the due date for filing the original return.
   (b)    Within three months from the final determination of any Federal tax liability affecting the taxpayer's City tax liability, such taxpayer shall make and file an amended City return showing income subject to the City tax based upon such final determination of Federal tax liability and pay any additional tax shown due thereon or make claim for refund of any overpayment. (Ord. 1981-47. Passed 4-27-81.)