New tax regime: Chapter-VIA deductions disallowed except limited exceptions; opt out in ITR to claim deductions. Under Section 115BAC the new tax regime disallows Chapter-VIA deductions (e.g., 80C, 80D, 80DD, 80G) except specified exceptions such as 80CCD(2), 80CCH and 80JJAA; to claim Chapter-VIA deductions a taxpayer must opt out and choose the old tax regime by selecting the appropriate option in the ITR form when filing under section 139(1), observing due-date rules and providing Form 10-EA acknowledgement where required.