(a) Upon its own initiative, or upon the application of any party in interest on the ground of a change in conditions, including, for the purposes of AS 23.30.175, a change in residence, or because of a mistake in its determination of a fact, the board may, before one year after the date of the last payment of compensation benefits under AS 23.30.180, 23.30.185, 23.30.190, 23.30.200, or 23.30.215, whether or not a compensation order has been issued, or before one year after the rejection of a claim, review a compensation case under the procedure prescribed in respect of claims in AS 23.30.110. Under AS 23.30.110 the board may issue a new compensation order which terminates, continues, reinstates, increases, or decreases the compensation, or award compensation.
(b) A new order does not affect compensation previously paid, except that an award increasing the compensation rate may be made effective from the date of the injury, and if part of the compensation due or to become due is unpaid, an award decreasing the compensation rate may be made effective from the date of the injury, and payment made earlier in excess of the decreased rate shall be deducted from the unpaid compensation, in the manner the board determines.