Ann: MCL First to Release Australian Hemp Seed Oil Capsules, page-10

Ok so I did a bit of a quick search and you are indeed correct. ASX Guidance Note 14:

The MAO (ASX Market Announcement Office) duties are to determine "whether the announcement is likely to be market sensitive and therefore warrants a halt to trading under ASX Operating Rule 3301a"

There are also other references to this throughout the guidance note. So it seems QBL just submit the PDF market announcement either directly to the MAO or via the ASX Online platform, and the MAO then classifies each announcement as market sensitive or not.