Deduction under section 10AA extended for eligible units, altering qualifying period and deduction allowance conditions. The enactment substitutes the earlier reference to April 2006 with wording providing that for the period beginning April 2006 but before the prescribed cutoff, a deduction shall be allowed, and makes that substitution effective from the commencement date of the amendment, thereby changing the qualifying period and the statutory language determining entitlement to the deduction.