A note of explanation.
There were two Contests built for Elliott Steam Tug Co. London.
The sister, built in 1931 but was sold to an Italian company, Società Rimorchiatori Napoletani, Naples, in 1932 and renamed Vesuvio.
In 1943 she was seized by the German Navy.
In 1944 she was bombed and sunk at Livorno, salved and repaired.
1954 Renamed Vesuvius. In 1981 scrapped by Trirena SNC., Naples.
The other "sister" was built in 1933 and it was this vessel that was present at Dunkirk. It appears to be virtually identical but a little shorter at 100 ft in length.
So throughout the web site "Contest" usually refers to the 1933 vessel.