An annuity or pure endowment policy shall contain a provision that there shall be a period of grace of one month, but not less than 30 days, within which any stipulated payment to the insurer falling due after the first such payment may be made, subject at the option of the insurer to an interest charge thereon at the rate specified in the policy but not exceeding six percent per annum for the number of days of grace elapsing before such payment, during which period of grace the policy shall continue in full force. In case a claim arises under the policy on account of death prior to expiration of the period of grace before the overdue payment to the insurer or the deferred payments of the current policy year, if any, are made, the amount of such payments, with interest on any overdue payments, may be deducted from any amount payable under the policy in settlement. [1967 c.359 § 405]