I wonder if it depends on the charges then as to what is done. The trials I was on were not Brisbane courthouse but in Queensland still.Interesting.
We were free to do as we pleased while trial was underway. We were escorted to the pavement, warned about approaches and talking in public, and then allowed to roam at will. Some ate together, others spent the time alone wandering town for a feed.
Only once deliberating were we forced to stay in the room as a group with lunch supplied.