Question & Answer
A leap second is a one-second adjustment that is occasionally applied to Coordinated Universal Time (UTC) in order to keep its time of day close to the mean solar time. Without such a correction, time reckoned by Earth's rotation drifts away from atomic time because of irregularities in the Earth's rate of rotation. Since this system of correction was implemented in 1972, 26 such leap seconds have been inserted. The most recent one happened on June 30, 2015 at 23:59:60 UTC. A leap second will again be inserted on December 31, 2016, at 23:59:60 UTC.
If your IBM i Operating System is configured to to utilize the NTP time protocol service via the network, the leap second will be adjusted by this service.
If your IBM i Operating System is not configured to utilize the NTP time protocol service via the network, you will need to make the leap second adjustment manually by changing the QTIME system value.
18 September 2020