Probably using up existing stock. Technically they wouldn't have been producing the "lawsuit" design, just getting rid of what they already had.
SB-series are the exception as they were economy models. The pro level L-1000 and L-2000 switched in early '83. The F-100 guitar switched over a little later in the year. Also, there was no CBS-Fender law suit regarding the early headstocks though there may have been the threat of one. IIRC, George Fullerton designed the new headstock (with the little point) to be less "generic" as well as less "Fendery" while giving G&Ls a unique look and avoiding any potential for a law suit. The SB-series basses and SC-series guitars probably flew under CBS-Fender, and later FMIC's, radar screen as sales were miniscule compared to Fender sales. GG