I'm going to post training times for other roles as well just to give an idea of things.
Most Army positions require basic recruit training.
> Army Recruit Course
> Duration: Approximately 12 weeks.
> Location: Kapooka, Wagga Wagga, NSW.
> During training, you will take part in physical training, weapon handling and shooting, first aid, drill and field craft. You'll be challenged both mentally and physically.
In some cases it might be assumed that Ukrainian soldiers already had done an equivalent kind of training.
Infantry
> Army Recruit Course
> Duration: Approximately 12 weeks.
> Infantry Course
> Duration: Approximately 3 months.
So 6 months or 3 if just Infantry but as it's the most basic position I'll assume 6 months.
Artillery Operator(we use M117s)
> Army Recruit Course
> Duration: Approximately 12 weeks.
> Basic Combat Communications Course
> Duration: Approximately 1 week.
> Royal Australian Artillery Common Induction Training
> Duration: Approximately 3 weeks.
> Gun Grade 1 Course
> Duration: Approximately 6 weeks.
So 22 weeks if they are fresh, 10 weeks for just artillery. Which is actually a bit less than it takes to train Infantry, surprising.
https://www.defencejobs.gov.au/jobs/army/artillery-operator
Armoured vehicle crew
> Army Recruit Course
> Duration: Approximately 12 weeks.
> Armoured Crewman Common Course: 71 days
> Following completion of the common training you will begin your vehicle specific training which will take between 21 and 41 days to complete on either tank, APC or the CRV. The vehicle you are assigned to will be dependant on the service needs of the Armoured Vehicle Crew Regiments.
So 14 to 28 weeks.
https://www.defencejobs.gov.au/jobs/army/armoured-vehicle-crew