(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:

Provided that in case of other person referred to in section 153C, the period of limitation for making the assessment or reassessment shall be the period as referred to in clause (a) or clause (b) of this sub-section or nine months from the end of the financial year in which books of account or documents or assets seized or requisitioned are handed over under section 153C to the Assessing Officer having jurisdiction over such other person, whichever is later:

Provided further that in the case where the last of the authorisations for search under section 132 or for requisition under section 132A was executed during the financial year commencing on the 1st day of April, 2018,—

 (i)  the provisions of clause (a) or clause (b) of this sub-section shall have effect, as if for the words "twenty-one months", the words "eighteen months" had been substituted;

(ii) the period of limitation for making the assessment or reassessment in case of other person referred to in section 153C, shall be the period of eighteen 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 or twelve months from the end of the financial year in which books of account or documents or assets seized or requisitioned are handed over under section 153C to the Assessing Officer having jurisdiction over such other person, whichever is later:

Provided also that in the case where the last of the authorisations for search under section 132 or for requisition under section 132A was executed during the financial year commencing on or after the 1st day of April, 2019,—

 (i)  the provisions of clause (a) or clause (b) of this sub-section shall have effect, as if for the words "twenty-one months", the words "twelve months" had been substituted;

(ii)  the period of limitation for making the assessment or reassessment in case of other person referred to in section 153C, shall be the period of twelve 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 or twelve months from the end of the financial year in which books of account or documents or assets seized or requisitioned are handed over under section 153C to the Assessing Officer having jurisdiction over such other person, whichever is later:

Provided also that in case where the last of the authorisations for search under section 132 or for requisition under section 132A was executed and during the course of the proceedings for the assessment or reassessment of total income, a reference under sub-section (1) of section 92CA is made, the period available for making an order of assessment or reassessment shall be extended by twelve months:

Provided also that in case where during the course of the proceedings for the assessment or reassessment of total income in case of other person referred to in section 153C, a reference under sub-section (1) of section 92CA is made, the period available for making an order of assessment or reassessment in case of such other person shall be extended by twelve months.

(2) The authorisation referred to in clause (a) and clause (b) of sub-section (1) shall be deemed to have been executed,—

(a)  in the case of search, on the conclusion of search as recorded in the last panchnama drawn in relation to any person in whose case the warrant of authorisation has been issued; or

(b)  in the case of requisition under section 132A, on the actual receipt of the books of account or other documents or assets by the Authorised Officer.

(3) The provisions of this section, as they stood immediately before the commencement of the Finance Act, 2016, shall apply to and in relation to any order of assessment or reassessment made before the 1st day of June, 2016:

Provided that where a notice under section 153A or section 153C has been issued prior to the 1st day of June, 2016 and the assessment has not been completed by such date due to exclusion of time referred to in the Explanation, such assessment shall be completed in accordance with the provisions of this section as it stood immediately before its substitution by the Finance Act, 2016 (28 of 2016).

Explanation.—In computing the period of limitation under this section—

 (i)  the period during which the assessment proceeding is stayed by an order or injunction of any court; or

(ii)  the period commencing from the date on which the Assessing Officer directs the assessee to get his accounts audited under sub-section (2A) of section 142 and—

 (a)  ending with the last date on which the assessee is required to furnish a report of such audit under that sub-section; or

 (b)  where such direction is challenged before a court, ending with the date on which the order setting aside such direction is received by the Principal Commissioner or Commissioner; or

(iii) the period commencing from the date on which the Assessing Officer makes a reference to the Valuation Officer under sub-section (1) of section 142A and ending with the date on which the report of the Valuation Officer is received by the Assessing Officer; or

(iv)  the time taken in re-opening the whole or any part of the proceeding or in giving an opportunity to the assessee of being re-heard under the proviso to section 129; or

(v)  in a case where an application made before the Income-tax Settlement Commission is rejected by it or is not allowed to be proceeded with by it, the period commencing from the date on which an application is made before the Settlement Commission under section 245C and ending with the date on which the order under sub-section (1) of section 245D is received by the Principal Commissioner or Commissioner under sub-section (2) of that section; or

(vi) the period commencing from the date on which an application is made before the Authority for Advance Rulings under sub-section (1) of section 245Q and ending with the date on which the order rejecting the application is received by the Principal Commissioner or Commissioner under sub-section (3) of section 245R; or

(vii) the period commencing from the date on which an application is made before the Authority for Advance Rulings under sub-section (1) of section 245Q and ending with the date on which the advance ruling pronounced by it is received by the Principal Commissioner or Commissioner under sub-section (7) of section 245R; or

(viii) the period commencing from the date of annulment of a proceeding or order of assessment or reassessment referred to in sub-section (2) of section 153A, till the date of the receipt of the order setting aside the order of such annulment, by the Principal Commissioner or Commissioner; or

(ix) the period commencing from the date on which a reference or first of the references for exchange of information is made by an authority competent under an agreement referred to in section 90 or section 90A and ending with the date on which the information requested is last received by the Principal Commissioner or Commissioner or a period of one year, whichever is less; or

(x)  the period commencing from the date on which a reference for declaration of an arrangement to be an impermissible avoidance arrangement is received by the Principal Commissioner or Commissioner under sub-section (1) of section 144BA and ending on the date on which a direction under sub-section (3) or sub-section (6) or an order under sub-section (5) of the said section is received by the Assessing Officer,

shall be excluded:

Provided that where immediately after the exclusion of the aforesaid period, the period of limitation referred to in clause (a) or clause (b) of this sub-section available to the Assessing Officer for making an order of assessment or reassessment, as the case may be, is less than sixty days, such remaining period shall be extended to sixty days and the aforesaid period of limitation shall be deemed to be extended accordingly:

Provided further that where the period available to the Transfer Pricing Officer is extended to sixty days in accordance with the proviso to sub-section (3A) of section 92CA and the period of limitation available to the Assessing Officer for making an order of assessment or reassessment, as the case may be, is less than sixty days, such remaining period shall be extended to sixty days and the aforesaid period of limitation shall be deemed to be extended accordingly:

Provided also that where a proceeding before the Settlement Commission abates under section 245HA, the period of limitation available under this section to the Assessing Officer for making an order of assessment or reassessment, as the case may be, shall, after the exclusion of the period under sub-section (4) of section 245HA, be not less than one year; and where such period of limitation is less than one year, it shall be deemed to have been extended to one year.