(19A)the annual value of any one palace in the occupation of a Ruler, being a palace, the annual value whereof was exempt from income-tax before the commencement of the Constitution (Twenty-sixth Amendment) Act, 1971, by virtue of the provisions of the Merged States (Taxation Concessions) Order, 1949, or the Part B States (Taxation Concessions) Order, 1950, or, as the case may be, the Jammu and Kashmir (Taxation Concessions) Order, 1958:Provided that for the assessment year commencing on the 1st day of April, 1972, the annual value of every such palace in the occupation of such Ruler during the relevant previous year shall be exempt from income-tax;