Section 2-A-405. Excused Performance. (1)  Subject  to  Section  2-A-404  on  substituted  performance,  the  following rules apply: (a) delay in delivery or nondelivery in whole or  in  part  by  a lessor  or  a  supplier  who  complies with paragraph (b) and subsection (2) is not a default under the lease  contract  if performance  as  agreed  has  been  made impracticable by the occurrence of a contingency the nonoccurrence of which was  a basic  assumption  on which the lease contract was made or by compliance in good  faith  with  any  applicable  foreign  or domestic governmental regulation or order, whether or not the regulation or order later proves to be invalid. (b) if  the causes mentioned in paragraph (a) affect only part of the lessor's or the supplier's capacity to perform, he or she shall allocate production and deliveries  among  his  or  her customers  but  at  his  or  her  option  may include regular customers not then under contract for sale or lease  as  well as his or her own requirements for further manufacture. He or she may  so  allocate  in  any  manner  that  is  fair  and reasonable. (2) The lessor seasonably shall notify the lessee and in the case of a  finance lease the supplier seasonably shall notify the  lessor  and  the  lessee,  if  known,  that  there  will  be  delay or nondelivery and, if  allocation is required under subsection (1) (b), of the estimated  quota  thus made available for the lessee.