400.2-616. (1) Where the buyer receives notification of amaterial or indefinite delay or an allocation justified undersection 400.2-615 he may by written notification to the seller asto any delivery concerned, and where the prospective deficiencysubstantially impairs the value of the whole contract under theprovisions of this article relating to breach of installmentcontracts (section 400.2-612), then also as to the whole,
(a) terminate and thereby discharge any unexecuted portionof the contract; or
(b) modify the contract by agreeing to take his availablequota in substitution.
(2) If after receipt of such notification from the sellerthe buyer fails so to modify the contract within a reasonabletime not exceeding thirty days the contract lapses with respectto any deliveries affected.
(3) The provisions of this section may not be negated byagreement except in so far as the seller has assumed a greaterobligation under section 400.2-615.
(L. 1963 p. 503 ยง 2-616)