There don't seem to be any constraints on the buy-back in terms of price. There is a warning about solvency, though, so though we won't get any financials till 20th August I think we can be confident that the cash flow/balance is ok.
My guess is the large seller at 12c is a long-term holder who's been waiting for a chance to sell for sometime and wants to take advantage of the buy-back - though that doesn't start till April 16.
KKT Price at posting:
10.0¢ Sentiment: Buy Disclosure: Held