In 733, when Xiao Song was removed as chancellor (although still remaining as a high-ranked official) in the midst of his conflict with fellow chancellor Han Xiu (who was also removed as a result), Xiao Hua was made an imperial attendant (給事中, Jishizhong), and was soon promoted to be the deputy minister of public works (工部侍郎, Gongbu Shilang).
Toward the end of Emperor Xuanzong's Tianbao era (742–756), Xiao Hua was made the deputy minister of defense (兵部侍郎, Bingbu Shilang).
In 755, the general An Lushan rebelled at Fanyang Circuit (范陽, headquartered in modern Beijing), and soon established a state of Yan with him as emperor.
Xiao Hua sent secret correspondences to the Tang army agreeing to rise against Yan forces.
He was still considered tainted by his service as a Yan official, and he was demoted to be the acting Mishu Shaojian (秘書少監)—the deputy director of the Palace Library.
Li Fuguo was (briefly) completely in control, and Yuan Zai, in order to flatter him, accused Xiao of crimes.
Xiao was demoted to be the military advisor to the prefect of Xia Prefecture (峽州, in modern Yichang, Hubei).