Some countries rely heavily on tourism for their economy, and they make changes to their systems based on neighboring countries that drive their economy. For example, Samoa changed their driving direction in 2011 to align itself with Australia, with whom it conducts most of its business. And then they changed their time zone to align with Australia, jumping 21 hours ahead in the same year, losing a whole day.
The British Caribbean territory has historically followed Eastern Standard Time along with eastern U.S. states. Considering the fact that the sun sets at around 5pm in winter which happens to be their prime tourism season, Turks & Caicos will be able to provide more day light to its visitors.