Effect of amendment or repeal of law. The right to alter, amend or repeal ORS 543.010 to 543.610, or any part thereof, hereby is expressly reserved; but no such alteration, amendment or repeal shall affect any license theretofore issued under the provisions of ORS 543.010 to 543.610, or the rights of any licensee thereunder, unless expressly assented to by the licensee

ORS 543.320 — under Chapter 543.