Changes to Final Fantasy XIV's data centers were announced during the North American Final Fantasy XIV FanFest 2019. Earlier today the dates this change would take effect were announced via the official Final Fantasy XIV Lodestone website. North American and European servers will have different dates of implementation with the European restructuring taking place on April 2 to April 15 and the North American restructuring taking place on April 23 to March 6.
During this period players will be allowed to use a free World Transfer (which will allow you to pack up and move to a different server regardless of data center) to go to a new server of their choice if they wish to play elsewhere. However, there are some limitations to this as transfers to congested worlds such as Balmung and Gilgamesh will remain unavailable during this period. As always transferring to a preferred world will grant you the usual transfer bonuses which you can read about below.
Final Fantasy XIV: Shadowbringers will launch on July 2, 2019.