Looks like Jetstar spokespersons need to read their own passenger information on their web site
Wheelchairs - At the airport
All customers travelling with a wheelchair must check-in 2 hours prior to flights departing from a domestic terminal and 3 hours prior to flights departing from an international terminal.
Jetstar provides customers with a wheelchair in which to transfer at check-in.Jetstar customer service staff will assist in the transfer into the wheelchair, using Jetstar's approved transfer method of slide boards and slide cloths.
If required, a Jetstar customer service staff member will then escort a customer who requires wheelchair assistance from check-in through security to their boarding gate. If the customer is travelling with a carer/companion who is willing to escort the customer, a Jetstar customer service staff member will organise to meet the customer(s) at the boarding gate.
Baggage: The customer's wheelchair must be checked-in as baggage. Wheelchairs or mobility aids are carried free of charge on Jetstar services and are carried in addition to the baggage allowances applicable to the customer's travel itinerary. When a customer has more than one wheelchair or mobility aid(s), the second mobility aid will be charged as excess baggage. This includes wheelchairs, electric wheelchairs and electric scooters.
Even I can understand that.