“(1) Subclause (2) applies to any interim payments payable by a borrower for the tax year starting 1 April 2012 if 1 or more of those interim payments are due before the commencement of clause 4 of this schedule and 1 or more of those interim payments are due after that commencement.
“(2) In relation to interim payments to which this subclause applies, the term unpaid amount in sections 139 to 141 (as substituted by clause 4 of this schedule) is (despite section 5 as substituted by clause 1 of this schedule) taken to refer to an interim payment default (within the meaning of section 5 as in force before the commencement of clause 1 of this schedule) that has not been paid on or before the due date determined by section 5 (as so in force) and that has not been decreased, reduced, or written off by the Commissioner.
“(3) Subclause (4) applies to any instalments of an overseas-based repayment obligation payable by a borrower for the tax year starting 1 April 2012 if 1 or more of those instalments are due before the commencement of clause 4 of this schedule and 1 or more of those instalments are due after that commencement.
“(4) In relation to instalments of an overseas-based repayment obligation to which this subclause applies, the term unpaid amount in sections 139 to 141 (as substituted by clause 4 of this schedule) is (despite section 5 as substituted by clause 1 of this schedule) taken to refer to an overseas-based instalment default (within the meaning of section 5(2) as in force before the commencement of clause 1 of this schedule) that has not been paid on or before the due date determined by section 5(2) (as so in force) and that has not been decreased, reduced, or written off by the Commissioner.
“(5) Subclause (6) applies to any remaining repayments payable by a borrower for the tax year starting 1 April 2012 if 1 or more of those remaining repayments are due before the commencement of clause 4 of this schedule and 1 or more of those remaining repayments are due after that commencement.
“(6) In relation to remaining repayments to which this subclause applies, the term unpaid amount in sections 139 to 141 (as substituted by clause 4 of this schedule) is (despite section 5 as substituted by clause 1 of this schedule) taken to refer to the aggregate of those remaining repayments that have not been paid on or before the due date for the final of those remaining repayments and that have not been decreased, reduced, or written off by the Commissioner.”