The day after Xuu You severed Chen Xi's grain supply, Zhuge Liang went to report to Chen Xi about the most recent work, which, aside from constructing various fortifications, had not involved any significant events. Chen Xi had never intended to engage Xuu You in open battle; his aim was to stall the enemy.
As for why he knew the adversary was Xuu You, it was a deduction Chen Xi made based on certain intelligence reports. Although he did worry about Xuu You's sudden disappearance, it did not affect Chen Xi in the slightest. Even if the opponent did not appear, it would not concern him at all. His focus was on fortifying Linyi.
