Where a repudiatory breach of contract occurs, the innocent party must elect either to treat the contract as terminated (acceptance of the repudiation), or to treat it as continuing (affirmation of the contract).
Affirmation can only take place if the innocent party knows of the breach and of his right to choose between terminating and affirming the contract. Affirmation will often be implied if the innocent party knows of the breach and of his right to choose and acts in a manner consistent with treating the contract as continuing.
Although the innocent party does have time to elect whether to affirm or terminate, doing nothing for too long may be seen as an affirmation. Once an innocent party has affirmed a contract, the affirmation is irrevocable.