"Dunkerque" underwent another period of equipment inspections and gunnery testing after her return from the voyage that continued into May. From 1 to 4 July, she steamed to the English Channel to visit her namesake town, returning to Brest on 6 July by way of a stay in Saint-Vaast-la-Hougue on 4–5 July. George VI and Elizabeth were visiting Boulogne on 16 July, so "Dunkerque" left Brest that day in company with a group of warships to visit the British monarch there. "Dunkerque" got underway again on 22 July, bound for Calais, where she the British Royal Family as they left for home. On 1 September, "Dunkerque" was finally pronounced ready for service and was assigned to the Atlantic Squadron, becoming the flagship of its commander, "Vice-amiral d'Escadre" (Squadron Vice Admiral) Marcel-Bruno Gensoul.