Corned Beef King has exited Rockville Pike after a three-year run at a Liberty gas station off Twinbrook Parkway. Rent at that location was going “way up,” says owner Jon Rossler, who’s best known for his roving food trucks. Next home for the Corned Beef King: a new space on Stonestreet Avenue in Rockville, where Rossler plans to offer delivery, curbside pickup and catering.