| (a) | - | in respect of each assessment year falling within six assessment years and for the relevant assessment year or years referred to in clause (b) of sub-section (1) of section 153A, within a period of twenty-one months from the end of the financial year in which the last of the authorisations for search under section 132 or for requisition under section 132A was executed; |
| (b) | - | in respect of the assessment year relevant to the previous year in which search is conducted under section 132 or requisition is made under section 132A, within a period of twenty-one months from the end of the financial year in which the last of the authorisations for search under section 132 or for requisition under section 132A was executed: |