The Baby Bells are all looking at another round of middle management cuts and Nynex Corp says that up to 1,800 management positions will be cut by the end of 1992 as part of its previously announced cost reduction program that will eliminate 3,400 management positions throughout the family of companies by the end of next year: New York Telephone said employees were told that between 500 and 1,000 positions will be cut this autumn, and New England Telephone will cut between 350 to 400 workers by the year end, and Telesector Resources Group will cut its management by about 400.