Now after amendment, as per section 143(1D),
Notwithstanding anything contained in sub-section (1),
the processing of a return shall not be necessary, where
a notice has been issued to the assessee under subsection (2):

Provided that the provisions of this sub-section shall
not apply to any return furnished for the assessment year commencing on or after the 1st day of April, 2017
Further a new section inserted, As per Sec 241 A, For
every assessment year commencing on or after the 1st
day of April, 2017, where refund of any amount
becomes due to the assessee under the provisions of
section 143(1) and the Assessing Officer is of the
opinion, having regard to the fact that a notice has been issued under sub-section (2) of section 143 in respect of such return, that the grant of the refund is likely to adversely affect the revenue, he may, for reasons to be recorded in writing and with the previous approval  of the Principal Commissioner or Commissioner, as the case may be, withhold the refund up to the date on which the assessment is made.