There have not been any announcements that Revell will be doing the 2019 cars.
If Revell gets back in the modern NASCAR market, I don't see it happening before the Gen 7 cars are introduced in 2021. Just about everything with these cars will be different from the Gen 6 car, so any work done by Revell will not transfer to the new car.
There is a guy named Henrik who posts his work on Randy Ayers website. He created a new generation Mustang and may use it to make resin bodies. The body is supposed to work with the glue Fusion kit.
This maybe your only option for a while.