How long did the three brothers find each other in the romance of the Three Kingdoms?

Guan Yu was born in Jiexian County, Hedong County, and was a famous soldier at the end of the Eastern Han Dynasty. He was revered as a "warrior sage" by later generations, just like Confucius "Wen Sheng". Guan Yu followed Liu Bei around in his early days. After Battle of Red Cliffs was appointed as the prefect of Xiangyang by Liu Bei, Liu Bei entered Yizhou and Guan Yu stayed in Jingzhou. In 219, Guan Yu surrounded Xiangfan, and Cao Cao sent Yu Ban to reinforce him. Guan Yu captured Yu Ban and killed Pound, which was a great shock to China. Later, Cao Cao sent Xu Huang to reinforce him, and Soochow Lumeng attacked Jingzhou again. Guan Yu was caught between Scylla and Charybdis and was captured by Pan Zhang.

Liu Bei, Guan Yu and Zhang Fei became sworn brothers in The Romance of the Three Kingdoms, in which Liu Bei read the imperial conscription list at the city gate and sighed there. Zhang Fei said that the gentleman didn't want to serve the country, so he and Guan Yu were ready to join the army. Liu Bei said that the corruption of officials now, why work for others, why don't we form our own rebel army. Guan Yu and Zhang Fei thought what Liu Bei said was reasonable, so they decided to work with Liu Bei, and then they became brothers in the peach grove in Zhang Fei's backyard. After the swearing-in, a rebel army was formed to fight the Huang Jin army. Since then, he has made great achievements, established Shu Han, and Liu Bei became emperor. This matter was widely circulated and passed down as an eternal story.