It's usually bad business for a bank (Macquarie) to take over a mine.  I believe you hit the nail on the head, where the changes in management are concerned.  My best guess is this was to satisfy the lender.  On the other hand I feel more confident with Vito Belo (20 yrs of Rio Tinto experience).  
I too think the bottom might be in.  I too was a buyer.  GLTA