A procedural and interpretive rule, shall be considered by the board for adoption not later than six months after the close of public comment and a notice of withdrawal or adoption shall be filed in the state register within that period. Failure to file such notice shall constitute withdrawal and the secretary of state shall note such failure in the state register immediately upon the expiration of the six-month period.
A procedural or interpretive rule may be amended by the board prior to final adoption without further hearing or public comment. No such amendment may change the main purpose of the rule. If the fiscal implications have changed since the rule was proposed, a new fiscal note shall be attached to the notice of filing. Upon adoption of the rule (including any such amendment) the board shall file the text of the adopted procedural or interpretive rule with its notice of adoption in the state register and the same shall be effective on the date specified in the rule or thirty days after such filing, whichever is later.