Each health maintenance organization shall have a plan for handling insolvency which allows for continuation of benefits for the duration of the agreement period for which premiums have been paid and continuation of benefits to members who are confined on the date of insolvency in an inpatient facility until their discharge or expiration of benefits. The commissioner shall approve such a plan if it includes:

(1) Insurance to cover the expenses to be paid for continued benefits after insolvency;

(2) Provisions in provider contracts that obligate the provider to provide services for the duration of the period after the health maintenance organization's insolvency for which premium payment has been made and until the enrolled participants' discharge from inpatient facilities;

(3) Use of insolvency reserves established under RCW 48.46.240;

(4) Acceptable letters of credit or approved surety bonds; or

(5) Any other arrangements the commissioner and the organization mutually agree are appropriate to assure that benefits are continued.