A variance between an allegation in a petition under section 705 or a pleading in a proceeding under section 706, and the proof, is not material unless it is so substantial as prejudicially to mislead the board or any party. If a variance is not material, the hearing officer may admit such proof and the facts may be found accordingly.
N.Y. Comp. Codes R. & Regs. Tit. 12 § 253.17