Headlining the changes is the significant improvement in terms of straight-line performance for the Model S 75 and 75D, which both can now accelerate from 0-100km/h a full second quicker than before - 4.6 seconds and 4.4 seconds, down from 5.8 seconds and 5.4 seconds respectively.
The same goes for the larger Model X 75D - available only in dual-motor 'D' guise - which can now sprint from 0-100km/h in a claimed 5.2 seconds - down from 6.2 seconds.
The performance improvements have been achieved through a combination of software and hardware updates, meaning the changes apply to new vehicles from the factory rather than current examples already on the road.
Additionally, the Model S 100D and Model X 100D cut the benchmark 0-100km/h sprint time to 4.3 seconds and 4.9 seconds respectively - down from 4.4 and 5.0 seconds.
Meanwhile, the Model X also sees the introduction of a new seven-seat option that allows the second and third rows to fold completely flat, however the Australian seating specification remains unchanged.
Tesla's local arm has confirmed the updated Model S and Model X ranges are available to order now, with the changes already shown on the company's online configurator.
Kicking off the Model S range, the 75 starts at $121,183 plus on-road costs "after incentives and petrol savings", while the Model X 75D is listed at $145,143 plus on-roads.