When they were trying to figure out the date when Kira Kozuke no Suke would be home, Oishi received information through his friend KADA no Azumaro, who was a scholar of Japanese classical literature, that the tea ceremony would be held on January 30 at Kira's residence since Azumaro was often invited to Kira's place to teach how to compose poetry and give lectures on "Genji Monogatari" (The Tale of Genji) as well as "Ise Monogatari" (The Tales of Ise).
吉良上野介在邸確実の日を探る必要もあったため、しばしば吉良邸に招かれて、『源氏物語』や『伊勢物語』を進講したり、歌の指導をしていた国学者荷田春満が、大石の友人であったので春満を通じて吉良邸茶会が12月14日にあるという情報を入手。