The entry will be a full DJR car, running as a third Shell V-Power-backed entry alongside the #11 and #17 Mustangs.
While the Supercars Commission approved the car for both the Sandown 500 and the Bathurst 1000, DJR has opted to limit the programme to the Bathurst race and sit out Sandown.
When asked by Motorsport.com why that was, DJR CEO explained that the lateness of the final decision to press on with the wildcard made getting to Sandown too difficult.
"It was probably more scheduling; we made the decision late," said Noble.
"We had a great appetite and buy-in from our partners, but it was probably just a bridge too far to get to Sandown. It was more a timing issue."
The wildcard has been facilitated by a tweak to the superlicence rules, which allows drivers who finished in the top three of Super3 one season only need three Super2 starts the following year to qualify.
Allen's wildcard hopes relied on that change, another factor in the team running out of time to add Sandown to its schedule.
"The timing of the superlicence change was also a big factor in not being able to schedule Sandown in as well," confirmed team principal Ben Croke.
Instead DJR will use September to give the wildcard drivers plenty of testing laps as they look to acclimatise to the Gen3 hardware.
De Silvestro's Supercars experience is all in COTF/Gen2 cars while Allen is racing a Gen2 Holden in Super2.
"We've put together a pretty tight [testing] programme, there's a lot going on," said Croke.
"Pretty much for the whole month of September, and then into October, Simona will be joining us here in Australia. Kai will be spending some time up here [in Queensland] as well.
"The first run for them will be the fourth of September and [Queensland Raceway], then with all three cars on the fifth of September, and then we'll squeeze another one, which will be a lot on process and procedure and endurance race stuff, just before Bathurst.
"It's all a very tight timeframe, but it's about making sure their time in the Gen3 car is maximised leading into Bathurst so they are familiar with all of the surroundings of the team and the car."
DJR will be pitted with fierce rivals Triple Eight for the Bathurst 1000, with the two wildcards sharing a boom.
Croke is confident there will be no issues with the joint project though, with conversations with T8 team manger Mark Dutton on the integration already in full swing.
"That's work in progress. Mark Dutton and myself have had some conversations already about how it's going to work out," he explained.
"They are doing Sandown, so how we integrate and mix that is a lot of work in progress.
"But I think with being positioned next to each other for seven or eight years now, we've worked together in pitlane amazingly well despite being the fiercest of rivals throughout that time and competing head-to-head.
"The working relationship remains and I have no doubt both teams will be professional and go about it the right way."
