600, which used same-day qualifying, and the Pennzoil 150 Xfinity race, which had Friday practice as the Indianapolis Motor Speedway moved the event to the road course as part of an INDYCAR doubleheader), and starting order was initially determined by either a random draw, divided into segments of the owners' points standings as of that race, for single race meetings, and for the second race in the same meeting, the finishing order from the previous race with the top 20 inverted. Similar to rules used when rain cleaned the rubber off the circuit between the last session and the race, refueling of cars was prohibited until a predetermined safety car situation ("competition caution") at a specific lap (between lap 10 on road courses to lap 50 on short tracks) announced during the conference call that drivers, crew chiefs, and officials participated during the week that replaced the competitors' meeting held on race morning. Some Truck Series races did not use them because of their shorter lengths. The safety car situation was used in order to allow for extended adjustments of vehicles. If a safety car is called before the predetermined lap, refueling was still prohibited until the predetermined lap safety car, unless NASCAR determines they are within enough laps to allow for the rule to be cleared. Starting in August with the Daytona road course round, NASCAR launched a new procedure based on performance. The new procedure is a three-pronged, weighted system formula taking into account the team owners' current place in the points standings, drivers' previous race finish, and drivers' fastest lap in the previous race. The driver with the lowest total number is awarded the pole, the second-lowest starts on the outside of the front row, and so on. After four weeks, and six races had been conducted with only the Charlotte and Atlanta races having limited spectators in condominiums on the circuit, NASCAR announced on 9 June that invited guests will be admitted at the Dixie Vodka 400 in Homestead. Homestead featured 1,000 members of the U.S. military from the South Florida area (representing United States Southern Command and the Homestead Air Reserve Base). The GEICO 500 at Talladega was the first round to feature paid spectators, with a limit of 5,000 spectators combined in the grandstands and backstretch camping, featuring priority to local ticketholders. The ARCA Menards Series General Tire 200 and NASCAR Xfinity Series Unhinged