(1) Upon approval of a redistricting plan by three of the voting members of the commission, but not later than ((January 1st))November 15th of the year ending in ((two))one, the commission shall submit the plan to the legislature.

(2) After submission of the plan by the commission, the legislature shall have the next thirty days during any regular or special session to amend the commission's plan. If the legislature amends the commission's plan the legislature's amendment must be approved by an affirmative vote in each house of two-thirds of the members elected or appointed thereto, and may not include more than two percent of the population of any legislative or congressional district.

(3) The plan approved by the commission, with any amendment approved by the legislature, shall be final upon approval of such amendment or after expiration of the time provided for legislative amendment by subsection (2) of this section whichever occurs first, and shall constitute the districting law applicable to this state for legislative and congressional elections, beginning with the next elections held in the year ending in two. This plan shall be in force until the effective date of the plan based upon the next succeeding federal decennial census or until a modified plan takes effect as provided in RCW 44.05.120(6).

(4) If three of the voting members of the commission fail to approve and submit a plan within the time limitations provided in subsection (1) of this section, the supreme court shall adopt a plan by March 1st of the year ending in two. Any such plan approved by the court is final and constitutes the districting law applicable to this state for legislative and congressional elections, beginning with the next election held in the year ending in two. This plan shall be in force until the effective date of the plan based on the next succeeding federal decennial census or until a modified plan takes effect as provided in RCW 44.05.120(6).