The first reported cases were in December.
https://www.who.int/news-room/detail/27-04-2020-who-timeline---covid-19
The November case wasn't identified until later.
https://www.livescience.com/first-case-coronavirus-found.html
FTA: On Dec. 27, Dr. Zhang Jixian, head of the respiratory department at Hubei Provincial Hospital, reported to health officials in China that a novel coronavirus was causing the disease; by that day, it had infected more than 180 individuals. (Doctors may not have been aware of all of those cases at the time, but only identified those cases after going back over the records, the Morning Post reported.)