One would expect a rise in traffic with the promotional push tied to "Free" and "Listen Up!"
The stats for April 20 don't appear accurate though. Haley appeared on American Idol March 23 and it seems unlikely traffic would drop by 2/3 in the month following that. She kept busy that month:
http://haleyfans.com/forumdisplay.php?fid=41
HaleyFans saw a slight rise in traffic from March to April followed by a similar sharp rise from April to May:
http://siteanalytics.compete.com/haleyfans.com/
Haleyrcentral.com is the top "fan" site in Google results. It shows a traffic pattern for those months similar to HaleyReinhart.com:
http://siteanalytics.compete.com/haleyrcentral.com/