Complex sentence: For a time he commuted to Cleveland, but eventually shifted to Squire, Sanders and Dempsey's Washington, D. C. office, remaining with the firm until he retired in 1987.
Split into simpler sentences: For a time he commuted to Cleveland, but he eventually shifted to Squire, Sanders and Dempsey's Washington, D. C. office. He stayed with the firm until he retired in 1987.