Very little. I've seen some, but they're as relevant as the lot above.
The North Brazil Counter Current provides the NW push into the LKP 40NM radius circle, and at some point the North Atlantic Equatorial Counter Current forces a turn to the North. The Brazilian current does that (turns north) and around 4N backs to the west, while the Counter Current veers to the east. The whole thing is extremely fluid (no pun intended!) and the if, where, when and how are very much a lottery.
Its the complex geophysical forces in the equatorial region that are stretching the known boundaries. Backtracking in theory should be easier than forecasting, as you have the immediate past environmental history to work with. In this case its knowing how to apply the history that's the killer.
mm43