Ann: Trading Halt, page-4

If the results are positive (which is likely), requesting a trading halt is a sign of a professionally run organisation, as it represents their desire to prevent trading based on information not available to the public. If the results are negative, it hopefully acts to defend against SP plummeting on re-open because it gives them time to release the negative news in a controlled manner, with a plan of attack to maintain value for holders into the future.