On the way down, AC90 was late, so connecting to AC96 was immediate and no time for lounge access.
On the way up, AC97 was early and we had about 2 hours in the lounge.
It really depends on timing between the two flights but you can access the old *A lounge (now name-sponsored by Banco Safra). The Amex lounge is also open and accessible (I stuck my head in), but in my opinion the Banco Safra has better privacy corners.
Please note that you may have to backtrack - once you pass intermediate security, you may come out halfway down the terminal wing and you have to walk against the pedestrian flow into the centre part where the lounges are.