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 UCC 1-207 provides: 'A party who with explicit reservation of rights performs or promises performance or assents to performance in a manner demanded or offered by the other party does not thereby prejudice the rights reserved. Such words as 'without prejudice,' 'under protest,' or the like are sufficient.'

The Official Comment to this section provides in part: '1. This section provides machinery for the continuation of performance along the lines contemplated by the contract despite a pending dispute, by adopting the mercantile device of going ahead with delivery, acceptance, or payment 'without prejudice,' 'under protest,' 'under reserve,' 'with reservation of all ...