On June 1, Seller and Buyer contracted in writing for the sale and purchase of Seller's cattle ranch (a large single tract), and to close the transaction on December 1. Assume the following facts. Buyer unequivocally repudiated the contract on August 1. On August 15, Seller urged Buyer to change her mind and proceed with the scheduled closing on December 1. On October 1, having heard nothing further from Buyer, Seller sold and conveyed his ranch to Rancher without notice to Buyer. On December 1, Buyer attempted to close under the June 1 contract by tendering the full purchase price to Seller. Seller rejected the tender. If Buyer sues Seller for breach of contract, Buyer will probably 
win, because Seller failed seasonably to notify Buyer of any pending sale to Rancher.  win, because Seller waived Buyer's August 1 repudiation by urging her to retract it on August 15.  lose, because Buyer did not retract her repudiation before Seller materially changed his position in reliance thereon by selling the ranch to Rancher.  lose, because acceptance of the purchase price by Seller was a concurrent condition to Seller's obligation to convey the ranch to Buyer on December 1.