Lico posted a huge post on instagram, my japanese isn't good at all but I kinda understood that she's leaving, she's very grateful for the time she spent with "ayu-chan" and it was like a dream come true, I'm not really sure but I think she says something about her health as well, I really liked her, gonna miss her.
https://www.instagram.com/p/BKiv7K8hSgT/ That's the post