For more than a decade, a tacit understanding among China’s top rulers has ensured the ruling Communist party does not become a gerontocracy. That understanding, known as qishang baxia or “seven-up, eight-down”, dictates that only leaders 67 or younger can ascend to or remain in top posts, while those 68 or older must retire when the party changes guard every five years.

But as China prepares to enter a “selection year” under the leadership of a very unconventional president, Xi Jinping, there is increasing speculation he may try to dispense with the retirement convention entirely.

If so, it will be the biggest test yet of his authority over the party and further distinguish him from his predecessors Hu Jintao and Jiang Zemin, who took a “first among equals” approach during their presidencies.