63. Substituted for the sub-heading and section 246 by the Direct Tax Laws (Amendment) Act, 1987, w.e.f. 1-4-1989. Prior to its substitution, sub-heading along with section 246 were amended by the Finance Act, 1964, w.e.f. 1-4-1964, Finance Act, 1966, w.e.f. 1-4-1967, Taxation Laws (Amendment) Act, 1970, w.e.f. 1-4-1971, Taxation Laws (Amendment) Act, 1975, w.e.f. 1-4-1976, Finance (No. 2) Act, 1977, w.e.f. 10-7-1978, Finance Act, 1979, w.e.f. 1-6-1979, Taxation Laws (Amendment) Act, 1984, w.e.f. 1-10-1984, Finance Act, 1984, w.e.f. 1-4-1985, Finance Act, 1987, w.e.f. 1-4-1988 and Finance Act, 1988, w.r.e.f. 1-4-1988/ 1-6-1987.