At the end of this year, the employer may rebut the presumption that the union represents the majority of workers, either by demonstrating that the union does not in fact enjoy a majority, or by having a good faith doubt based on sufficient objective evidence that the union has lost the majority (NLRB v. Curtin Matheson Scientific, 494 U.P. 775, 110 p. Ct. 1542, 108 L. Ed. 2d 801 ,1990). In cases where the employer doubts that a union has majority support, the employer may “early withdraw” the union`s recognition by insisting on a collective agreement that will expire at the end of the certification year (Rock-Tenn Co. . . .