Peak day prediction of 2019-20 winter holidays travel

According to this site Shinkansen Timetable’s independent survey, the train congestion peaks during coming winter holidays (December 27, 2019 – January 5, 2020) will be December 28 for outbound trains and January 4 for inbound ones.
Seat availability around the expected peak days
Checking the actual seat availability data at the night of December 12, we draw charts shown below indicate seat availability of around the peak days on Tokaido, Sanyo and Kyushu Shinkansen.
On the graphs, horizontal axes mean hours of departure from 6 to 24 and vertical the number of Nozomi, Mizuho, Hikari, Sakura and Tsubame trains. The bar of blue shows under-occupied trains, yellow near capacity and red full occupancy. So it may easy to book trains at the hours with stretching blue bar.
The seat availability changes from moment to moment. Visit the site of JR Cyber Station and get up-to-the-minute details.
Tokaido Shinkansen
outbound (Tokyo → Shin-Osaka)December 27, 28, 29 from the left.
January 3, 4, 5 from the left.
Sanyo Shinkansen
outbound (Shin-Osaka → Hakata)December 27, 28, 29 from the left.
January 3, 4, 5 from the left.
Kyushu Shinkansen
outbound (Hakata → Kagoshima-Chuo)December 27, 28, 29 from the left.
January 3, 4, 5 from the left.