People Wrote Diaries in the Three Kingdoms, and Boss Cao Was Confused

The first year of Xingping was the third year that Chen Cong traveled through time. He has been writing a diary for three consecutive years and is about to complete the task issued by the system and return to the original world. Suddenly, in the cold and snowy afternoon of mid-winter, he received for the first time a sealed letter from the Yanzhou Prefectural Shepherd's Mansion. The person who signed it was none other than Cao Cao, who was currently in control of Yanzhou. After Chen Cong read it, he kept the appointment as scheduled!