As mentioned awhile back they had filming to do in North Carolina as well as Illinois. It was unclear whether they would do that during Zac's time off or when. But now we know after they wrapped in Illinois they moved to North Carolina and were filming today. Guessing but I think they are maybe catching some of the interior or close-up car shots they need for the ARCA race. They did only have a brief time to film in Iowa, and no time during the race. But who knows?
Anyway, here is a shot of them prepping Dean's car today: