429.56. The board, on an application, may review or revoke any decision or order it has made(1) where a new fact is discovered which, had it been known in time, could have warranted a different decision;
(2) where a party, owing to reasons considered sufficient, could not be heard;
(3) where a substantive or procedural defect is of a nature likely to invalidate the decision.
In the case described in subparagraph 3 of the first paragraph, the decision or order may not be reviewed or revoked by the commissioner who made the decision or order.