(a)(1) Promptly after the order for relief under this chapter, the United States Trustee shall appoint one disinterested person that is a member of the panel of private trustees established under section 586(a)(1) of title 28 or that is serving as trustee in the case immediately before the order for relief under this chapter to serve as interim trustee in the case.
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(b) The service of an interim trustee under this section terminates when a trustee elected or designated under section 702 . . . qualifies under section 322 of this title.