Upon the entry of a stop order under any part of RCW 21.20.280, the director shall promptly notify the issuer of the securities and the applicant or registrant that the order has been entered and of the reasons therefor and that within twenty days after the receipt of a written request the matter will be set down for hearing. If no hearing is requested within twenty days and none is ordered by the director, the director shall enter written findings of fact and conclusions of law and the order will remain in effect until it is modified or vacated by the director. If a hearing is requested or ordered, the director, after notice of and opportunity for hearings to the issuer and to the applicant or registrant, shall enter written findings of fact and conclusions of law and may modify or vacate the order. The director may modify or vacate a stop order if the director finds that the conditions which prompted its entry have changed or that it is otherwise in the public interest to do so.