Meinberg NTP LANTIME 320 automatic command for UTC Time Zone changing

Hello.

I am trying to syncronize a NTP Server Meinberg LANTIME model 320 at Chile, but over here we have the condition that the time at some poing of the year is delayed 1 hour.

So we use (UTC-4) and also (UTC-3).

How could I make to make this change automatically at a specific date? is there a command to use? where?

If you could explain tech support.

Thanks.