§12A-2-616.

§12A-2-616.
   
   (1) Where the buyer receives notification of a material or indefinite
   delay or an allocation justified under the preceding section he may by
   written notification to the seller as to any delivery concerned, and
   where the prospective deficiency substantially impairs the value of
   the whole contract under the provisions of this article relating to
   breach of installment contracts (Section 2-612), then also as to the
   whole,
   
   (a) terminate and thereby discharge any unexecuted portion of the
   contract; or
   
   (b) modify the contract by agreeing to take his available quota in
   substitution.
   
   (2) If after receipt of such notification from the seller the buyer
   fails so to modify the contract within a reasonable time not exceeding
   thirty (30) days the contract lapses with respect to any deliveries
   affected.
   
   (3) The provisions of this section may not be negated by agreement
   except in so far as the seller has assumed a greater obligation under
   the preceding section.