She's announced she's terminating her concurrent position in Team K.
akb48-daily.blogspot.ca - Yamamoto Sayaka will appear on Web TV "Hibana"- http://akb48-daily.blogspot.ca/2015/12/yamamoto-sayaka-will-appear-on-web-tv.html- http://www.oricon.co.jp/news/2064238/full/
AKB48 Daily - Yamamoto Sayaka to publish Essay Collection [the book will be released on 29 March 2017]- http://akb48daily.blog.fc2.com/blog-entry-1266.htmlEDIT: http://www.cdjapan.co.jp/product/NEOBK-2064921