tz libraries shipped a new version for the tzdata update, as they do more or less every time the database is updated (monthly or so). 9 months lead time is actually pretty good, consider: April 29th the Egyptian government announced they'd go on DST on July 7th, with no further information until June 27th when Parliament proposed to abolish DST and passed a (apparently non-binding) vote for that on June 28th, following which the Egyptian government announced they wouldn't go on DST after all on July 4th.