Acording to this decree http://www.planalto.gov.br/ccivil_03/_Ato2007-2010/2008/Decreto/D6558.htm The DST period in Brazil now on will be from the 3rd Oct Sunday to the 3rd Feb Sunday. There is an exception on the return date when this is the Carnival Sunday then the return date will be the next Sunday. Attached proposed diffs for the current Southamerica file and a script to calculate the exceptions. Regards, Frederico Neves