Stepping off the distance traveled between ACARS reports every ten minutes from the coast of Brazil would indicate straight and level flight at a nicely constant speed right up to the very last report. Small variations in speed are likely an artifact of the minute-wide time stamps.
It would seem that the A/C was just about exactly where it should have been when it last reported at 0210 (although we don't know its altitude, and it was at the time 3 miles left of track). If it had initiated a steep bank leftward, that would have occurred within the minute prior to 0210. Earlier, the reported distance traveled between reports at 0200 and 0210 would have been measurably less.
Until 0209 it would seem there was no deviation from track nor WX avoidance. If they were precisely on track at 0209, at a GS of 7.8nm/min (0.13nm/sec) it would have taken maybe 30 to 45 seconds to bank steeply away from the track to a distance of 3nm. So banking left remains a possibility prior to AP Disconnect.
The situation went pear-shaped suddenly within seconds either way of the 0210 ACARS report. Put the location of that last report at the center of a circle (2.98º N x 39.59º W) and estimate how far the A/C might have been able to fly (glide ratio maybe 20:1 clean but we know it wasn't clean, with ACARS reporting a high sink rate implied by cabin altitude warnings) in about 4.5 minutes without overspeed (A/C reported intact at impact) while the cockpit attempted to regain control from underspeed/overspeed stall, catastrophic wind shear, or whatever caused the upset. An exercise for one of you A330 drivers. Draw the circumference. Shouldn't be far. Should find the hull inside.
Now GS could have been cranking up during the 10 minutes after 0200 as the pitots began reading lower and lower and thrust was automatically increased to compensate, and the A/C could have initiated a turn back from further up the track and been returning in reverse when the 0210 report was sent. In any event, we know where the A/C was at 0210 and we infer from the missing expected ACARS message that the A/C was in the water less than five minutes later.
Draw the circle.
GB