In addition to amounts otherwise available to carry out this part, up to $50,000,000 in any fiscal year may be obligated against appropriations under subchapter I of this chapter (other than this part) for use in providing assistance in accordance with the authorities and general policies of section
2292 of this title. Amounts subsequently appropriated under this part with respect to a disaster may be used to reimburse any appropriation account against which obligations were incurred under this subsection with respect to that disaster.