Section 12A. Any person, or the legal guardian of any person, who may be entitled to accidental death benefits under the provisions of section nine may, during and within the period of one year next succeeding the death of the member in service, avail himself of the allowance provided under option (d) of section twelve or under section twelve B in so far as it may be applicable and said person is eligible therefor, effective from the date of the death of the member and pending the determination of the application of said person for such accidental death benefits.

The filing of an application for accidental death benefits shall not arrest or suspend the payment of an allowance under option (d) of section twelve or under section twelve B; provided, however, that upon the first payment of any benefits provided under section nine payments under said option (d) or section twelve B shall cease and the amount of the first payment under said section nine shall be reduced by a sum equal to the aggregate allowance paid to said person under said option (d) or section twelve B.