The leap second is added at the same point in time regardless the timezone your server is configured to use. So if you're GMT+3, the leap second will be inserted at 03:00 local time.
From the answer: "The reason this is occurring before the leap second is actually scheduled to occur is that ntpd lets the kernel handle the leap second at midnight, but needs to alert the kernel to insert the leap second before midnight. ntpd therefore calls adjtimex sometime during the day of the leap second, at which point this bug is triggered."
From the answer: "The reason this is occurring before the leap second is actually scheduled to occur is that ntpd lets the kernel handle the leap second at midnight, but needs to alert the kernel to insert the leap second before midnight. ntpd therefore calls adjtimex sometime during the day of the leap second, at which point this bug is triggered."