§ 4-2-615 - Excuse by failure of presupposed conditions.
               	 		
4-2-615.    Excuse by failure of presupposed conditions.
    Except  so far as a seller may have assumed a greater obligation and subject to  the preceding section on substituted performance:
      (a)  Delay  in delivery or non-delivery in whole or in part by a seller who  complies with paragraphs (b) and (c) is not a breach of his duty under a  contract for sale if performance as agreed has been made impracticable  by the occurrence of a contingency the non-occurrence of which was a  basic assumption on which the contract was made or by compliance in good  faith with any applicable foreign or domestic governmental regulation  or order whether or not it later proves to be invalid.
      (b)  Where  the causes mentioned in paragraph (a) affect only a part of the  seller's capacity to perform, he must allocate production and deliveries  among his customers but may at his option include regular customers not  then under contract as well as his own requirements for further  manufacture. He may so allocate in any manner which is fair and  reasonable.
      (c)  The seller must  notify the buyer seasonably that there will be delay or non-delivery  and, when allocation is required under paragraph (b), of the estimated  quota thus made available for the buyer.