In a move which is said to have left observers surprised, Bank of China president Liu Jin took an earlier retirement this past weekend. 

According to CNBC, Liu's departure was made public on Sunday and was described as being undertaken "for personal reasons."

Liu only served as president for five months

Liu, who also served as the state-owned financial institution's vice chairman, will be temporarily replaced by Bank of China chairman Ge Haijiao until a permanent candidate can be found.

CNBC noted that prior to heading Bank of China, Liu had occupied high-ranking positions at ICBC, China Development Bank, and China Everbright Bank.

The South China Morning Post pointed out that the 57-year-old Liu is still three years away from China's official retirement age. What's more, he has only been at the helm of Bank of China for roughly five months.

The Post further observed that Liu was conspicuously absent from Bank of China's board meeting held earlier this month.

Former auditor linked to China Evergrande Group meltdown

The meeting was chaired by Ge, who revealed that Bank of China will henceforth use EY as its auditor rather than rival firm PwC China.

PwC China is currently subjected to a six-month ban by Chinese authorities and could face substantial fines due to its alleged role in the China Evergrande Group fiasco.

NPR reported that China Evergrande Group was regarded as the world's most valuable real estate company and had a prosperous business which involved preselling apartments to upper and middle class Chinese citizens.

However, a Hong Kong court ordered its liquidation at the start of this year after the debt-ridden firm failed to restructure the $300 billion it owed to investors.

Dexter Roberts serves as director of China affairs at the Mansfield Center at the University of Montana, and he called China Evergrande Group's demise  "a controlled implosion."

Former chairman pleads guilty to corruption charges

"China has known for a long time that their economy was imbalanced and too reliant on debt, with the real estate sector the most indebted industry of all and Evergrande the poster child for the most indebted company in that sector," Roberts told NPR.

Meanwhile, the Post pointed out that Liu's unexpected retirement is not the first time eyebrows have been raised at Bank of China.

Another example came in April when 62-year-old former chairman Liu Liange pleaded guilty to a slew of corruption charges.

Liu admitted to having illegally issued loans worth more than 3.3 billion yuan in exchange for bribes which totaled over 121 million yuan.