11 U.S.C. § 1121: Who may file a plan

The debtor may file a plan with a petition commencing a voluntary case, or at any time in a voluntary case or an involuntary case. Except as otherwise provided in this section, only the debtor may file a plan until after 120 days after the date of the order for relief under this chapter. a trustee has been appointed under this chapter; the debtor has not filed a plan before 120 days after the date of the order for relief under this chapter; or the debtor has not filed a plan that has been accepted, before 180 days after the date of the order for relief under this chapter, by each class of claims or interests that is impaired under the plan. Subject to paragraph (2), on request of a party in interest made within the respective periods specified in subsections (b) and (c) of this section and after notice and a hearing, the court may for cause reduce or increase the 120-day period or the 180-day period referred to in this section. The 120-day period specified in paragraph (1) may not be extended beyond a date that is 18 months after the date of the order for relief under this chapter. The 180-day period specified in paragraph (1) may not be extended beyond a date that is 20 months after the date of the order for relief under this chapter. extended as provided by this subsection, after notice and a hearing; or the court, for cause, orders otherwise; the plan and a disclosure statement (if any) shall be filed not later than 300 days after the date of the order for relief; and the debtor, after providing notice to parties in interest (including the United States trustee), demonstrates by a preponderance of the evidence that it is more likely than not that the court will confirm a plan within a reasonable period of time; a new deadline is imposed at the time the extension is granted; and the order extending time is signed before the existing deadline has expired.