Ann: Trading Halt, page-30

They halt so as to ensure there is no leak of details to the market before they can announce correct details. It may be as simple as translating a 50 page legal sales contract to something the market can digest and accept to the ASX rules of the "average person" understanding the content. There may also be disclosure limitations with the customer and so on that need to be altered. Furthermore D13 normally provide good announcements with few adjustments later on. Get announcements right the first time so all available information is there for market to digest, unlike some other companies.