(2) A mutual fire insurer shall use and issue only the standard form of policy required by ORS 742.202, except that:
(a) It is not required upon cancellation of the insurance policy or certificate of membership to return any part of any policy, certificate, membership or inspection fee that may have been charged.
(b) Where a definite part of the amount charged has been collected for and designated as an expense assessment, it may by bylaw determine the amount of refund that shall be made from such expense assessment.
(c) If it is on an assessment basis, levying assessments at such times and in such amounts as are necessary to defray its losses and expenses, it may provide by bylaw that no part of the assessments shall be returned.
(d) If it is organized for the insurance of a single class of risks and the assessment charged in a flat sum, it may provide in the insurance policy that no return assessment shall be paid upon cancellation. [Formerly 744.460 and then 743.681]