Signs which do not conform to the provisions of this title as of the effective date hereof shall be regarded as nonconforming signs subject to the following:
A. May not be structurally altered so as to prolong the life of the sign.
B. May not be expanded.
C. May not be reestablished after being discontinued for ninety (90) days.
D. May not be reestablished after damage if the estimated expense of reconstruction exceeds fifty percent (50%) of the replacement cost. (Ord. 1150, 4-2-1996)