4 as usual driver Ross Chastain was with Kaulig Racing for the event. He also ran ten Xfinity races for Shepherd Racing Ventures, failing to finish all but one as the team could not afford to run the full distance. Regardless, Cassill was able to qualify ninth in the Rhino Pro Truck Outfitters 300 at Las Vegas, the team's first top-ten qualifying effort since 2009. For the season-ending Ford EcoBoost 300 at Homestead, the team acquired enough sponsorship to enable the No. 89 to race the entire event. After qualifying 13th, Cassill finished 15th for the team's first completed race since 2013 and their first top-15 run since 2009. Although he was under contract for the 2020 season, Cassill lost his ride at StarCom to Quin Houff. Thus, he planned to run a full Xfinity schedule for Shepherd Racing Ventures pending funding. After skipping the opener at Daytona, Cassill entered the next three races before the season was impacted by the COVID-19 pandemic; sponsorship troubles due to the pandemic prevented SRV from returning for the rest of the year. Cassill instead served as a substitute in the event of a driver testing positive for COVID-19, though his duties were ultimately not required. In 2021, Cassill rejoined JD Motorsports and the No. 4 for the full Xfinity season. Ahead of the Dover race in May, Cassill swapped cars with JDM teammate Ryan Vargas and moved to the No. 6 to help it accumulate owner points. At the time of the switch, the No. 6 was 37th in owner points, which would have jeopardized its qualifying ability for later races. He scored no top tens, failed to qualify for the season finale at Phoenix, and finished 22nd in the final standings. On December 9, 2021, Kaulig Racing announced that Cassill would replace Jeb Burton in the No. 10, bringing sponsorship funding from Voyager Digital as it signed a two-year extension. His best run of the 2022 season would come at New Hampshire, leading 17 laps and finishing 3rd although he was disqualified in post-race technical inspection and would be scored 37th. On January 18, 2023, Cassill announced that he would not be returning to Kaulig Racing full-time for the 2023 XFINITY season. Motorsports career results Career summary NASCAR (key) (Bold – Pole position awarded by qualifying time. Italics – Pole position earned by points standings or practice time. * – Most laps