Uniform financial year adopted as previous year - returns accepted if tax and mandatory interest paid; scrutiny limited. Adoption of the financial year as the uniform previous year standardises accounting periods and creates transitional provisions including proportional increases to statutory monetary limits, enhanced depreciation for extended transitional years, adjusted residency day-counts, and an average-rate method to compute tax for extended periods. The new assessment regime accepts returns as filed where tax and mandatory interest are paid, permits only arithmetic and prima facie adjustments from return documents, imposes time limits for intimations, and levies additional tax where adjustments increase returned income.