Hi, My name is Phabiano Cardoso and i’m brazilian.
I need to inform for you that BRAZIL dont have anymore DST (Daylight Saving).
All devices that use us.pool.ntp.org are wrong times.
You can verify this information in site of Ministry of Mines and Energy os Brasilian governament
The NTP protocol only runs in UTC. The local time zone conversion is the work of YOUR device. So you should contact your device supplier for updates; if no updates are available (like the IANA tzdata or MS monthly rollup update) then your device is out of support and needs to be replaced.
NTP always supplies UTC time across the whole world. The local device is responsible for applying the correct local daylight savings. You need to contact the vendor of your device for an updated DST configuration file or instructions on how to update the DST setting on the device yourself.