I really don't know, unfortunately. However, there are quite a few of us here (including me) that have access to DL loads and could check for you close to your departure date. As a warning, GIG and GRU can have weight restrictions due to cargo for nonrevenue passengers, so that's a little risky, and BSB is surprisingly full considering how much time there is until then - maybe 2/3 full? However, once you get out of Brazil you should be ok until you try to get back into Brazil.