While Skywalker, Vader and their ilk seek an "energy field created by all living things [that] surrounds us, penetrates us and binds the galaxy together," the quintessential quest in anticipatory repudiation is to determine whether an unequivocal repudiation has occurred.
Both seeking to alter the deal and giving an unequivocal repudiation have their place, but the latter does not create anticipatory repudiation, while the former does.
As illustrated above, employing anticipatory repudiation entails risks.
Anticipatory repudiation also allows Vader to retract his unequivocal repudiation provided that Skywalker has not materially changed his position in the interim.
If Skywalker brings a lawsuit against Vader for breach of contract using the theory of anticipatory repudiation, then Skywalker must prove that he was ready, willing and able to perform his contractual obligations and would have done so, except for Vader's unequivocal repudiation.
Furthermore, if Vader unequivocally repudiates one contract, Skywalker cannot invoke anticipatory repudiation for any other contracts between them, though he would be wise to demand and receive Vader's adequate assurance of performance with respect to the remaining contracts.
For instance, if Skywalker moves to invoke anticipatory repudiation against Vader after learning that Princess Leia is only dealing with Vader on a COD-basis, it is conceivable that Skywalker is acting improperly.