Me. Rev. Stat. tit. 5, § 1666-A

The Legislature shall review a biennial or supplemental budget submitted to it in accordance with this chapter and enact a budget no later than 30 days prior to the date of adjournment prescribed in Title 3, section 2, except that, during the first year in office of a Governor-elect, the Legislature shall enact a budget no later than the first Friday in June.