Where a borrower and a moneylender or a credit receiver and a credit grantor concluded an agreement to treat, as from a stated date and for the purposes of payment, as one debt two or more than two amounts owing and payable in respect of principal debt and finance charges in connection with various money lending transactions or credit transactions, such transactions shall be deemed to have been terminated on such stated date, and thereupon the provisions of section 6C regarding a transaction which has been terminated and the calculation of the outstanding balance of the principal debt and finance charges thereon in respect of a transaction so terminated, shall apply mutatis mutandis in respect of any such agreement.