One side of the box features the date 2020.01.04 (which could indicate either January 04, 2020 or April 01, 2020) as well as 23:57 (11:57pm).
Anime director Tatsuki (Kemurikusa, Kemono Friends Season 1) has released a cryptic teaser video to his official Twitter feed that has fans clamoring at the idea of a TV anime version of his 2017 short anime film, Keifuku-san.
Another side of the box indicates the Japanese TV stations Tokyo MX, Tochigi TV, Gunma Television, and BS11.