Chinese are famous for taking the long view of history, and when it comes to leadership succession, they take a long view of the future. For the past fifty years China's top leaders have ruled with a clearly designated successor in the wings. In the old days few of the successors actually succeeded, but for the past 25 years the system has worked. General Secretaries of the Communist Party of China have served two five-year terms, and at the beginning of their second term there have been two—and only two—persons appointed to the Politburo Standing Committee (PBSC) who are young enough to be the successors of the Party and state leaders. So in 1997 and 2007 the top leaders were known for the next fifteen years.
Xi Jinping has started his second term by announcing a new era in Chinese politics, and evidently part of the new era is to leave open the question of his successor in 2022. No one on the new PBSC is young enough to meet the age requirement for successor, though there are several possibilities in the full Politburo. Does this mean that Xi plans to break precedent and take a third term himself? Or is he planning a more competitive selection process later in his term?
While Xi Jinping is likely to be powerful enough at the end of his second term to demand a third, he would be violating two current norms of succession: He would be a bit too old, and he would be staying on a bit too long. These norms are unwritten, but not insignificant. Wang Qishan, the anti-corruption tsar, abided by the age norm and is now retired from central leadership. More generally, most Party and state offices have age and term limits, and the Sixth Plenum declared in 2016 that there are no exceptions to the efficacy of Party discipline, and that exemplary conduct was expected of the Politburo and Central Committee. And Xi also holds the ceremonial office of President of the People's Republic of China, which does have a constitutional limit of two terms.
Xi has not designated a successor, but he might well be planning to have one. He now has the flexibility of watching the performance of the handful of potential successors over the next few years. The implicit competition to please Xi would strengthen his control, and the successful successor would begin his term (no women in the running) as the most loyal of Xi's loyal followers.
Ironically, Xi Jinping is likely to strengthen his authority as well as his continuing influence by planning to retire in 2022 rather than staying on for a third term. The third term would raise crises of expectations and deviate from the commitment that he has made to a new era of rule by law. His successor would be a loyalist chosen for his ability to follow Xi's direction. Time will tell, but in any case Xi will be in charge.