In the event that a member applies for an industrial disability retirement, the retirement system manager denies the application for industrial disability retirement benefits but grants an ordinary disability retirement and the member appeals the decision of the retirement system manager (denying the industrial disability benefits) to the retirement hearing commission, the retirement system manager shall pay ordinary disability benefits to the member pending the determination of the appeal. In such event and if the retirement hearing commission determines that the member is entitled to an industrial disability retirement, the disability retirement benefits shall be retroactive to the effective date of the ordinary disability benefits, with credit given to the retirement system for the amount of ordinary disability benefits already paid to the member. (Prior code § 34.13.1309)