Many countries make daylight saving time adjustments during the summer months. Typically, local time is advanced by one hour in the spring and set back one hour in the autumn.
However, NTP utilizes Universal Coordinated Time (UTC) rather than local time. UTC is not adjusted for local time zones or daylight saving (DST). Universal Coordinated Time is the same world-wide, regardless of location.
The Network Time Protocol, therefore, does not adjust clocks for the summer time switch over.
The operating systems of client computers are responsible for application of any daylight saving time adjustment. Therefore, a client computer located anywhere in the world is able to correctly synchronize to a NTP server regardless of location.