When the Thornycroft motor cruiser Irma was taken over by the Royal Navy in 1940, her owner, a Mr. Phillips, was in Madrid. Although she appears on several lists of ships that went to Dunkirk, there are no details of the part she played there.
After the war she was re-named Nottac and spent some time on the Clyde in Scotland. Then, in the '70's, she was used as a houseboat at Swan Island, Twickenham. Jerry Hulbert, who lived aboard, bought Irma from a couple who wanted to sail her to South Africa and fitted her out with all kinds of navigation equipment, an echo sounder and a set of signal flags, but at the last moment realised that a river cruising boat can't be adapted to cross an ocean. So she remained on the Thames until the summer of 2001.
She is now in the care of the Dunkirk Little Ships Restoration Trust at their base in Marchwood and has reverted to her original name of Irma. She is awaiting funds for restoration.
Source: 2, 3, 4, 5, 11 & 19