Looks like you lot need help with timezones.
GMT, by definition, does not change with the seasons. It is a universal time.
Time in the UK (and also Ireland and Portugal) is currently British Summer Time (BST), which is GMT+1.
Time in the rest of Western and Central Europe is currently Central European Summer Time, which is GMT+2. In the winter, CET is GMT+1.
Time in Eastern Europe (including Russia and Finland) is GMT+3 at the moment.
Time in North America is on Summer Time as well, with the East Coast therefore on GMT-4.
As I understand it, all of the major population centres in Brazil are on GMT-3 at the moment, and are obviously not using Daylight Saving Time at the moment. This means that Brazil is 4 hours behind the UK and 5 hours behind most of the rest of Europe.
Something else you should all bear in mind, is that you've managed to time the game to clash with all the other EU2 MP games on Sunday. It clashes with the Languish Game, EU Unleashed and Imperial Europe III. You might want to move the start time back a couple of hours so you don't find it impossible to find subs.