6 Where a determination pursuant to subsection 64(2) of the Act discloses that, in respect of the fiscal year for which the determination was made, the aggregate of the amounts on account calculated pursuant to subsection 3(1) as adjusted pursuant to section 4 and transferred into the Revenue Fund pursuant to subsection 67(2) of the Act, are
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(a) greater than the portion of the Nova Scotia share in respect of the fiscal year that relates to offshore sales tax, such overpayment shall be recovered by setting it off against an amount that may be payable or may become payable to Her Majesty in right of Nova Scotia pursuant to subsection 67(2) of the Act and subsection 3(1) of these Regulations; or