Limitation period extended: assessments may be made within twelve months of the financial year end when return follows an official order. Where a return is furnished consequent to an order under clause (b) of subsection (2) of section 119, an order of assessment may be made before the expiry of twelve months from the end of the financial year in which such return was furnished; cross references are expanded to include additional orders and revival provisions, and Explanation 1 is amended to extend a limitation period that would otherwise expire before month end to the end of that month.