bat.man: Very neat, I admire your style.
MerchantVenturer: "I imagine it was based on an assumption that because BA had closed several bases and BRS is one of the few remaining, it might be on a hit list."
I am more cynical than that. I imagine that one of the possible causes is folks who wish to see the share price move. I stress that this is simply movement of the price, for it does not matter if it is going up or down, to those that are trading shares, simple movement is where they make their money.
There will, of course, be other reasons behind such rumours but this is a prime candidate.