Thread:TheScienceWolf2/@comment-24053170-20200626173406/@comment-24053170-20200626174034

Also Cells at Work Black is in fact the second season-

On March 23, 2019, the official Twitter account announced that the series will receive a second season. The season will premiere in January 2021.

and then

In April 2020, the 20th issue of Morning magazine revealed that an adaptation of Cells at Work! Code Black would air in January 2021.

The release dates are the exact same. Which means that Cells At Work Black is in fact the second season of the anime.