S. 148A : Reassessment-Conducting inquiry, providing opportunity before issue of notice-Assessing Officer must first make inquiry with regard to information available after obtaining sanction from competent authority and thereafter, issue initial notice under clause (b) of section 148A calling for explanation on basis of which to decide whether case fit for reopening-Assessing Officer had issued initial notice under clause (b) as if inquiry is to be conducted under clause (a)-Notice bad in law.[S 148, 148A(b),148A(d), Art. 226]