Regarding the pollution spot it would be important to know how frequent the satellite crossed/pictured that area, i.e. if it took images the days before and after.
Having that information one could conclude from the preceding or succeeding images the relevance of this pollution for AF447.
As a standalone information it is not sufficient to derive or rule out the relevance.
Any one here knowing/having an idea in which intervals this satellite would take pictures of the same area ?
But to be honest I'm a bit surprised BEA ruled out the relevance of this image/information so quickly and decidedly !?
Ruling out information that does not match one's preconceived idea of how thimgs happened is not a good idea in investigations of any kind.
And for sure not in the investigation of a still largely unexplained aircraft accident....
Maybe they have further information which allowed them to rule it out for good reason ?! But why not pass that information to the public then ???