There had previously existed a post called "Kyoto Shugo," but in this case it was formally called "Kyoto Shugoshoku," and was pronounced "shugoshoku" in contrast to the Muromachi period's pronunciation, "shugoshiki."
過去にも「京都守護」の職名は存在したが、この場合は「京都守護職」と称するのが正式であり、守護職の読みも室町時代の“しゅごしき”に対して“しゅごしょく”と読む。