This year’s edition of the Liqui-Moly Bathurst 12 Hour will see a host of first and lasts as the Mountain welcomes new cars and says goodbye to others.

Of the 10 manufacturers represented in Class A, more than half of them are racing cars in a configuration we’re unlikely to see again.

In some instances it’s a case of a new evolution, an upgrade to the current model, but two of are planning on racing all-new cars once the European GT season kicks off later this year.

That means we’ll see brand new cars on the Mountain in early 2020.

Bentley is a year early with two of the latest spec Continentals set to race this time around.

We’ve never seen them Down Under before, since the Bathurst 12 Hour is in effect the final event of the 2018 GT season, rather than the first of 2019 (despite the fact it falls well into the new calendar year).

It has an all-new four-litre twin turbo V8, and takes in the Continental’s new body styling, which sees a more aggressive grille and front bar.

At the other end of their lifespans are the McLaren 650S GT3, and the Aston Martin Vantage V12 GT3.

McLaren has already raced its new-for-2019 720S GT3, with Shane van Gisbergen taking the wheel in the Gulf 12 Hours.

The new car has been developed in-house at McLaren, where the 650S was produced under licence.

It will continue to sport a four-litre twin-turbo V8 making it mechanically very similar to the car it replaces, and maintains the tradition of using a carbon-fibre tub as the 650S and MP4-12C before it did.

Around that, McLaren claims 90 percent of the car has been either modified or optimised from the road going 720S on which it’s based.

That old car’s biggest single event win was arguably the 2016 Bathurst 12 Hour, with van Gisbergen at the wheel along with Jonathan Webb and Alvaro Parente. So, big shoes to fill there.

Similarly Aston Martin will this year introduce the successor to the Vantage V12 GT3.

Gone is the V12 replaced with a Mercedes-based four-litre twin-turbo V8.

The big open mouth has also disappeared, with a more tapered front end featuring a more stylised trademark grille mounted far lower.

The car was given a debut of sorts at the 24 Hours of Le Mans, running in an all-Aston Martin supporting event to the French classic last July.

New cars aside, rules in GT racing allow manufacturers to release one update kit during a car’s life.

However, there are a number of other tweaks that find their way onto cars over the years, with little differences up and down pit lane evident this year over last.

And there are more to come, with a swathe of manufacturers poised to release comparatively major updates to their cars over the next 12 months.

Out of Japan, Nissan has developed a new GT-R NISMO GT3.

Visually it shares a number of cues with the car it replaces but under the skin are a few subtle changes.

The twin-turbo charged engine, for a start, is mounted further back to aid weight distribution, and it has new brakes too. It’s a case of evolution versus revolution.

Also set to race in its current guise for the last time is the Audi R8 LMS GT3, with an update pack set to be introduced post-Bathurst.

Those changes centre around aerodynamics, most obviously the front bar, with the company claiming that it provides more consistent and predictable downforce by simplifying the airflow to the rear end.

There are also stronger components underneath, from the gearbox to bearings and the clutch.

Porsche will this year introduce an update to the 911 GT3 R, which it claims will be more powerful and better in terms of drivability.

The German marque last year introduced some aerodynamic tweaks, with the dive planes on the front corners of the car the most obvious way to pick it.

For next year the updates continue outside and in, with a bigger duct in the bonnet scooping the hot air out of the radiator mounted in the nose of the car.

Lamborghini has also been busy fettling the Huracan GT3, with the Italian marque introducing an update kit, called the EVO, to the car.

Aerodynamically the update is a step forwarded, but so too in terms of drivability and ease of setup it claims.

Those gains come as a result of a bigger rear wing, a new front splitter and diffuser, and tweaks to the V10 engine mounted in the middle of the car.

This year also marks the first year that we should see the BMW M6 GT3 in its current form.

The current car came into being for the 2016 season, replacing the Z4 GT3, with a 4.4-litre twin turbo V8.

There was an Evo package available last year which included revisions to the suspension, drivetrain, brakes and aero, which BMW claimed was aimed at making the car easier to drive and more reliable.

All up it promises to deliver another new-look field to the Mountain next year, just as it has done this year courtesy of the new Bentley Continental.

It goes to show that even in the tightly controlled world of GT racing, to start still is to go backwards.