Section 3404 - Return of unearned premium(a) Cancellation initiated by insurer.--Unearned premium must be returned to the insured not later than ten business days after the effective date of termination where commercial property or casualty risks are canceled in midterm by the insurer.(b) Cancellation initiated by insured.--Unearned premium must be returned to the insured not later than 30 days after the effective date of termination where commercial property or casualty risks are canceled in midterm by the insured.(c) Repayment on estimated basis.--Where the amount of premium to be returned cannot be calculated precisely within the required time period for return of premium because:(1) the policy was written on the basis of an estimated premium; or(2) the policy was issued subject to a premium audit; the unearned premium shall be returned to the insured on an estimated basis. Upon the insurer's completion of computation of the exact premium to be returned, an additional return premium or charge shall be made to the named insured or insureds within 15 days of the final computation.(d) Applicability to retrospective rating plans.--This section shall not apply to policies written on a retrospective rating plan.(e) Liability for fine.--For a period of 60 days from the effective date of this act, insurers failing to comply with subsection (a) shall not be subject to any fine under section 8(2) .1986, July 3, P.L. 396, No. 86, § 4, imd. effective.