Unexplained-income taxation requires valid deeming classification, while enhanced special rates apply prospectively under the stated effective-date framework.
Section 115BBE applies only where income is validly assessed under the deeming provisions for unexplained income; a surrender, disclosure or addition alone is insufficient. The assessing authority must identify the relevant provision and reject the explanation of nature and source where required. The special computation denies deductions, allowances and loss set-off against qualifying income. The Rajasthan High Court treated the enhanced rate introduced with effect from 1 April 2017 as prospective, preserving the earlier rate for financial year 2016-17. Penalty under section 271AAC depends on a valid section 115BBE determination.