Shaddows - 5:12 pm on Apr 7, 2010 (gmt 0)
What does this mean? Which filter has been applied to these sites when you couldn't not correlate the events because every keyword seems to has it's own timing?
Screenshots again. Then, when it settles down, compare to the mid-update, and the pre-update SERPS. Find whats changed- see if the bounderies of helpnow's classes have shifted to include/exclude new groups.
Once you do this for a couple of shifts you will see patterns mid-shift. Then, you can have "hunch-test" pages in situ for the anticipated system, allowing you to get a jump on the competition.