Under RCW 48.19.050, an insurer may authorize a bureau to file forms on its behalf. This section applies to members or subscribers that have granted filing authority to a bureau. Bureau members or subscribers must follow instructions provided by the bureau when they implement, delay or nonadopt a bureau form filing that has been approved by the commissioner. The insurer must make a filing with the commissioner if it delays the effective date, nonadopts or changes the bureau filing in any way. The filing must:

(1) Include a statement of changes proposed by the insurer;

(2) Provide the filing number used by the bureau when it filed the forms; and

(3) Be received by the commissioner in a timely manner.

(4) For purposes of this section, "timely" means:

(a) Before the bureau effective date if the filing is made under RCW 48.18.100; or

(b) Thirty days after the bureau effective date if the filing is made under RCW 48.18.103.