Word comes through to expect action from the north and orders are given to re-orientate. A few pairs work quickly to move branches and logs, creating further positions to observe and, soon, defend from.

The platoon, about 30-strong, readies. A signal: Australian soldiers are spotted 300 metres away. One minute passes, maybe more. The heightened level of alert seems to draw out time. Then the fight begins. 

The air erupts with sound. A line of camouflaged bodies makes its way up the incline.

Alternating between a run and a crawl they clear their way through the enemy positions with blank rounds, metre by metre. "Are you dead?" yells one. "Yes," comes a reply. Others in uniform walk calmly, offering feedback to the advancing group.

The situation may be manufactured, but it's to serve an important purpose.

After the 10-minute faux firefight, the situation is assessed. There are wounded soldiers to treat - friends, foes - and prisoners to process. It's early afternoon but there is still plenty to do before setting up for the night, even then there will be watch shifts.

This is Exercise Jacka Run, a challenging eight-day training activity involving more than 500 Australian Army Reserve soldiers in the lead up to July's Talisman Saber - an even larger joint US-Australian exercise. 

Though the 90-person combat team tasked with clearing the hilltop position hails largely from regional Victoria, there are units from Tasmania and South Australia among Battle Group Jacka too.

Over the course of the exercise they will complete objectives in a simulated environment across a portion of the 37,000 hectare Puckapunyal Military Area.

The following morning, Jacka's in-field headquarters need to be relocated. There are communication issues with Exercise Control.

A convoy of vehicles crawl up a steep incline to the top of a hill - our wheels spin on the loose gravel before engaging four-wheel drive.

Once stopped, Lieutenant-Colonel Mark Neich - commanding officer of both the battle group and the 12/40 Battalion within it, The Royal Tasmania Regiment - describes the purpose of the exercise as part of a "road to ready". 

"We'll achieve our readiness status by completing Talisman Saber - that is our next exercise as a battle group," Neich says.

During that exercise, the group will work alongside other elements of the Australian Army's 1^st Brigade. If successful, they will become the reinforcing reserves. "Once ready, our soldiers may be deployed."

Since a large overhaul of the army under Plan Beersheba, announced in 2011 and finalised in 2017, the reserves have held a more active role.

Reserve elements, paired with one of the three restructured combat brigades, complete a three-yearly "readiness" cycle involving two years of training and one as the certified deployable force, allowing for better integration of the part- and full-time personnel.

For Lieutenant William Richman, another member of the 12/40 RTR, this reality means the exercise is taken seriously.

"Even though we are preparing for Exercise Talisman Saber, we are training for if we do need to go to war," he says.

A final-year teaching student at the University of Tasmania, the Launceston-based Richman hopes to land a job like any other graduate, but sees himself in the reserves until he retires.

"It's pretty tough, but it is all part of the job," he says of the exercise. "So depending on what position you have, whether you're in infantry ... or cavalry or in transport and logistics, you've all got a pretty tough role to make sure that the whole battle group can work and function."

After spending the morning carrying out patrols over almost five kilometres of the battleground, Combat Team Charlie take a quick break. They are about to make contact with refugees, played by another group, to assess for threats and help move them away from the danger.

Corporal James Fagg of 12/40 RTR - and UTAS marketing in his civilian life - is one of the team, and says activities like this help them prepare for any operations they may be part of in the near future.

"Be they civil military liaison - so disaster relief in Australia ... peacekeeping in the Solomon Islands, to conventional warfare."

Containing about 30 soldiers from the Tasmanian contingent, this group also includes an equal number of their British Army Reserve counterparts - The 3rd Battalion, Royal Anglian Regiment - as part of an exchange program to strengthen a 50-year connection.

Lance-Corporals Tyron and Reece Fuller made the journey from the United Kingdom and say there are a lot of similarities between the two armies - certain tactics around weather being one of the main differences.

As twins in different roles, Tyron and Reece's situation has caused some laughs. "You get people saying 'I need you for this'," Tyron recalls with a smile. "Well that's not me, that's my brother."

Soon, it's time to move out.

The combat team haul heavy packs back onto their shoulders and head through the scrub, the sun beating down, twigs snapping underfoot, onto their next objective.

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