15(1)Section 63 does not apply in relation to returns and assessments made for prescribed accounting periods beginning before 1st April 1990 but subject to that shall have effect in relation to the cases referred to in the following sub-paragraphs subject to the modifications there specified.
(2)Subsection (1) shall have effect in a case falling within paragraph (b) of that subsection where the assessment was made on or before 10th March 1992 with the substitution of “20 per cent.” for “15 per cent.”.
(3)In relation to any prescribed accounting period beginning before 1st December 1993 section 63 shall have effect with the substitution—
(a)for the words in subsection (2) following “exceeds” of “either 30 per cent. of the true amount of the VAT for that period or whichever is the greater of £10,000 and 5 per cent. of the true amount of VAT for that period.” and with the omission of subsections (4) to (6); and
(b)for the words in subsection (8) from “subsections” to “statements” of “subsection (7) that the statement by each of those returns is a correct statement”.
(4)In relation to any prescribed accounting period beginning before 1st June 1994 section 63 shall have effect with the substitution for subsection (3) of the following subsection—
“(3)Any reference in this section to the VAT for a prescribed accounting period which would have been lost if an inaccuracy had not been discovered is a reference to the aggregate of—
(a)the amount (if any) by which credit for input tax for that period was overstated; and
(b)the amount (if any) by which output tax for that period was understated;
but if for any period there is an understatement of credit for input tax or an overstatement of output tax, allowance shall be made for that error in determining the VAT for that period which would have been so lost.”and in subsection (8) for “this section” there shall be substituted “subsections (5) and (7) above”.