Various sources have reported that The Rookery inside WindTraders ran out of their stock Banshees. This occurred only 5 to 6 days after Pandora opened to the public, and they had sufficient stock during the passholder previews! I believe this must be due to popularity. Sources also say they expect a restock in three weeks or so.
Source:
http://www.wdwinfo.com/news-stories/windtraders-is-all-out-of-banshees-in-the-rookery/
Source:
http://www.wdwinfo.com/news-stories/windtraders-is-all-out-of-banshees-in-the-rookery/