Nos. 1035, 1255, Dockets 90-4135, 90-4151. Argued February 8, 1991. Decided April 10, 1991. Abner P. Slatt, New York City, and John R. Hunt, Atlanta, Ga. (Slatt and Lane, New York City, Stokes, Lazarus Carmichael, Atlanta, Ga., of counsel), for petitioner-cross-respondent. Karen L. Arndt, Washington, D.C. (Paul J. Spielberg, Deputy Asst. Gen. Counsel for the N.L.R.B., Jerry M. Hunter, General Counsel for the N.L.R.B., Aileen A. Armstrong, Deputy Associate General Counsel for the N.L.R.B., of counsel)