Holding that while an employer is not obligated to discharge permanent replacements to make room for returning economic strikers, the employer must place the former strikers on a preferential recall list
In Randall v. NLRB, 687 F.2d 1240 (8th Cir. 1982), this court observed that "[t]he existence of a temporary job is not the equivalent of a vacancy to which a striker should have been reinstated."