Trading halts are used by listed companies to manage their continuous disclosure obligations - ie. when they become aware of market sensitive information of a material nature which is not yet publicly known. It allows them to inform the market of this new (yet pre-existing) information in a fair and transparent way.
You're suggesting SGH request a TH in anticipation of market information that does not yet exist. This is inconsistent with the underlying principle and I doubt it would be accepted
SGH Price at posting:
63.0¢ Sentiment: Hold Disclosure: Held