Magic is a global game and sometimes the politics of the world influence the battle between Planeswalkers.
Today it was announced that due to the political situation in Argentina that Grand Prix Buenos Aires, originally scheduled for March 16-18, 2016, has been canceled. The tournament organizers recommended visiting Buenos Aires in the coming years but no date was provided.
In the same announcement, the date of Grand Prix Kuala Lumpur was moved. Originally taking place in August 2015, it was moved to October 7-9 2016. The government requires use of the space, so Grand Prix Kuala Lumpur will take place a fortnight later, October 21-23, 2016. It's format has changed to Standard.
Update (10.14.15): Director of Organized Play Helene Bergeot posted this in regards to the canceled Grand Prix Buenos Aires:
Regarding the announcement about GP Buenos Aires being cancelled, we're currently looking at a new location in South America. Stay tuned
— Helene Bergeot (@HeleneBergeot) October 14, 2015