Why does java tzupdater add leap seconds?

java,date,datetime,time,leap-second

I have now closely looked at the release-notes of TZUPDATER and IANA (in its experimental location github/eggert/tz): TZUPDATER says: The Mexican state of Quintana Roo, represented by America/Cancun, will shift from Central Time with DST to Eastern Time without DST on 2015-02-01 at 02:00. Chile will not change clocks in...