Captain George Johnstone took over in early 1779 and served in the English Channel. On Johnstone's advancement to commodore in April that year, Captain Robert Nicholas took over as "Romney"s commander, though she remained part of Johnstone's squadron and flew his broad pendant. After a refit she returned to sea in 1779 as Sir John Ross's flagship, with Johnstone back as captain. She was involved in the operations in the Channel during the attempted Franco-Spanish invasion, after which she sailed to Lisbon. On 11 November 1779 she and captured the 34-gun Spanish frigate "Santa Margarita", which was subsequently taken into the navy as . With Johnstone's return to the post of commodore in December 1779, command passed to Captain Roddam Home, though Johnstone remained aboard. On 1 May 1780, "Romney" was involved in an incident with the cartel ship "Sartine". "Romney" captured two French ships off Cape Finisterre in July, the 38-gun on 1 July, and the 18-gun "Perle" five days later on 6 July.