Effective from Sunday, October 25th at 02:00 local time, times in Mexico will be backward one hour. This due to the biannual change from summertime to wintertime, in which the time zone moves forward in April and moves backward in October.
In the Mexican Republic, the time change applies progressively throughout all of the territory; first in the time zone of the Center, an hour later in the time of the Mountain, and lastly, in the Pacific zone.
There are some exceptions to this, noted below:
The state of Sonora does not participate in this change. It only has a one-time zone throughout all the year, in order to keep on par with the state of Arizona
The state of Quintana Roo does not participate in this change since 2015. The hour stays the same through all the year. The reason was the effective and efficient use of infrastructure destined to the tourism of sun and beach.
The state of Baja California and the other 28 entities of the front fringe of northern Mexico is ruled by the American summertime zone, which changes the second Sunday of March. This way, the change does not affect the commercial activities they keep with adjacent cities