Any other provisions of law to the contrary notwithstanding:

(1) Any person who served as a volunteer firefighter prior to March 3, 1955, and who began receiving retirement benefits at a later date from the fund, based on the board of trustees' belief that such person was eligible for such benefits, but whose retirement benefits were ceased or canceled by the board of trustees based upon its subsequent realization that such person was not in fact eligible for such benefits; or

(2) Any person who left service as a volunteer firefighter after receiving written notice from the secretary-treasurer of the fund that he was eligible for retirement benefits except for not having reached the age of 60 years, which written notice was later determined by the board to be erroneous,

shall be eligible to receive the retirement benefits under this chapter in the same manner as if such service had been rendered in a class eight or better fire department, regardless of the fact that such service was not rendered in a class eight or better fire department.