The payment shall be made as provided in
section 6904 of this title and shall include an amount payable under section 6904. However, an amount computed but not paid because of the first sentence of subsection (b) and the 2d sentence of subsection (c) of section 6904 shall be carried forward and applied to future years in which the payment would not otherwise equal the amount of real property taxes assessed and levied on the land during the last fiscal year before the fiscal year in which the interest was acquired until the amount is applied completely.