HONG KONG—A closely monitored national security case involving 47 Hong Kong democracy activists charged with conspiracy to commit subversion, most of whom have been in custody for more than six months, will resume on Nov. 29, a judge ruled on Thursday. Magistrate Peter Law in the Western Kowloon Court ruled more time was needed for pre-trial legal proceedings to be finalized. Hong Kong laws prohibit media from publishing the contents of such proceedings. The case is then expected to move to the High Court. National security crimes are punishable by up to life in prison, but only higher courts have the authority to give such long sentences. The West Kowloon Court can only give sentences of up to three years. The 47, who include opposition politicians, are among more than 100 people who Hong Kong police have arrested under a national security law that Beijing imposed on the former British …