On the morning of Saturday, 1 June 1940, during the peak of small craft traffic en route to Dunkirk, Lieutenant H. Simouth Willing of the Twickenham Sea Cadet Corps arrived at Ramsgate from the Thames aboard Rummy II. He was placed in command of the vessel and assigned a naval crew. Under intense shellfire, they reached Dunkirk towing two ships' lifeboats. The lifeboats were used to ferry approximately 140 men back during the night.

The pulling boats, although occasionally towed by powered craft, faced significant challenges navigating the strong tidal streams near the beaches. They were instructed to transport their full loads to the nearest available transport vessel. Lieutenant Willing noted with pride the steadiness of his crew under heavy fire, stating: "We found the tug we were serving after a long row, under heavy fire and I am pleased to report my crew by name for steadiness under close fire."

In 1946, Rummy II was sold by the Admiralty to Jack Pritchard, who kept her at Lock Island, Marlow. In 1949, Dr. Charles Collins acquired a share in the vessel and cruised with his family from Lechlade, near the source of the Thames, down to the sea. After 1956, Rummy II operated in coastal waters from Faversham in Kent.

Eight years later, David Teare became a part-owner and remains the only surviving member of that ownership group. Some years prior, Leonard Walsh, another part-owner, transported the vessel to Birkenhead for refurbishment but passed away before work commenced. Following his death, interest in the vessel waned, and its whereabouts became unknown. Consequently, Rummy II is now officially considered lost.