If you assumed that Wilsons covering BTA, and issuing such a...

If you assumed that Wilsons covering BTA, and issuing such a negative report, they would have liquidated some of their positions and their clients' as well, which could explain the triggered sell off.
Couple that with short term profit taking, stop loss triggers and voila today's ratty stock action!
It will be interesting to see if there are any take ups at this level by larger buyers looking at getting a leg in...