It may also correspond to the frequence of findings of debris and bodies in the area North of the last known position as doumented in the BEA report.
This one shows the total debris (white) and bodies (red) between 06-JUN-2009 and 18-JUN-2009.
This one only shows debris and bodies lovated on 06-JUN-2009.
The locations have incrementally moved to the North thereafter; however, this may be a hint about the gap between 01-JUN-2009 (occurence) and the first findings on 06-JUN-2009.
Denis